bluuebunny/crossref_metadata_2025 huggingface dataset:
Supplemental Irrigation with Brackish Water Improves Carbon Assimilation and Water Use Efficiency in Maize under Tropical Dryland Conditions
Authors: Cavalcante Eduardo Santos , Lacerda Claudivan Feitosa , Mesquita Rosilene Oliveira , de Melo Alberto Soares , da Silva Ferreira Jorge Freire , dos Santos Teixeira Adunias , Lima Silvio Carlos Ribeiro Vieira , da Silva Sales Jonnathan Richeds , de Souza Silva Johny , Gheyi Hans Raj
Published: April 2022

Dry spells in rainfed agriculture lead to a significant reduction in crop yield or to total loss. Supplemental irrigation (SI) with brackish water can reduce the negative impacts of dry spells on net CO2 assimilation in rainfed farming in semi-arid tropical regions and maintain crop productivity. Thus, the objective of this study was to evaluate the net carbon assimilation rates, indexes for water use efficiency, and indicators of salt and water stress in maize plants under different water scenarios, with and without supplemental irrigation with brackish water. The experiment followed a randomized block design in a split-plot design with four replications. The main plots simulated four water scenarios found in the Brazilian semi-arid region (Rainy, Normal, Drought, and Severe Drought), while the subplots were with or without supplemental irrigation using brackish water with an electrical conductivity of 4.5 dS m−1. The dry spells reduced the photosynthetic capacity of maize, especially under the Drought (70% reduction) and Severe Drought scenarios (79% reduction), due to stomatal and nonstomatal effects. Supplemental irrigation with brackish water reduced plant water stress, averted the excessive accumulation of salts in the soil and sodium in the leaves, and improved CO2 assimilation rates. The supplemental irrigation with brackish water also promoted an increase in the physical water productivity, reaching values 1.34, 1.91, and 3.03 times higher than treatment without SI for Normal, Drought, and Severe Drought scenarios, respectively. Thus, the use of brackish water represents an important strategy that can be employed in biosaline agriculture for tropical semi-arid regions, which are increasingly impacted by water shortage. Future studies are required to evaluate this strategy in other important crop systems under nonsimulated conditions, as well as the long-term effects of salts on different soil types in this region.
An Operational Downscaling Method of Solar-Induced Chlorophyll Fluorescence (SIF) for Regional Drought Monitoring
Authors: Hong Zhiming , Hu Yijie , Cui Changlu , Yang Xining , Tao Chongxin , Luo Weiran , Zhang Wen , Li Linyi , Meng Lingkui
Published: April 2022

Solar-induced chlorophyll fluorescence (SIF) has been shown to be a powerful proxy for photosynthesis and a promising indicator of drought monitoring, but the ability of high-resolution satellite-derived SIF for drought monitoring has not been widely investigated due to a lack of data. The lack of high spatiotemporal resolution satellite SIF hinders the resolution enhancement of SIF derived by downscaling or reconstruction algorithms. The TROPOspheric Monitoring Instrument (TROPOMI) SIF provides an alternative with finer spatiotemporal resolution. We present an operational downscaling method to generate 500 m 16-day SIF (TSIF) using Neural Networks over a local spatiotemporal window. The results showed that our method is very robust against overfitting, and TSIF has a strong spatiotemporal consistency with TROPOMI SIF (TROPOSIF) with R2=0.956 and RMSE=0.054 mWm−2sr−1nm−1. Comparison with another SIF product (CASIF) showed a spatiotemporal consistency with TSIF. Comparison with tower gross primary productivity (GPP) from AmeriFlux in California showed a strong correlation with R2 for multiple ecosystems ranging from 0.58 to 0.88. We explored the capacity of TSIF for monitoring a drought event in Henan, China, showing that TSIF is more sensitive to drought and precipitation compared to the Enhanced Vegetation Index. Our TSIF is a very promising indicator for regional drought monitoring.
Effect of Alfalfa-Derived Biochar on Anaerobic Digestion of Dairy Manure
Authors: Zeng Shengquan , Harris Riley , Kan Eunsung
Published: April 2022

Biochemical methane potential (BMP) tests were conducted for investigating the effects of alfalfa-derived biochar (AF-BC) on anaerobic digestion (AD) of dairy manure under various loading of AF-BC (0–10 g/L). BMP tests were performed at mesophilic temperature (37 °C) with the addition of AF-BC. Biogas and methane volumes and concentrations, water quality parameters (i.e., COD (chemical oxygen demand)), and volatile fatty acids (VFAs) were measured during the AD process. The addition of 1 and 5 g/L of AF-BC increased the biogas yields by 15.51% and 26.09% and methane yields by 14.61% and 26.88% compared with the control without addition of AF-BC. Additionally, the addition of AF-BC (1–10 g/L) decreased the lag phase by 7.14–22.45% and the CO2 content of biogas by 13.60–32.48%, while increasing the COD removal efficiency by 19.19–35.94% in the AD of dairy manure. Moreover, the addition of AF-BC also decreased total VFAs and acetic acid concentrations in the AD process. The increase in AD performance was mainly owing to the improvement of buffering ability of the AD system and direct interspecies electron transfer (DIET) among AD microorganisms resulting from the addition of AF-BC. In contrast, the addition of 10 g/L AF-BC did not show any obvious improvement in biogas and methane yields in the AD of dairy manure, possibly because of toxic effects from excessive addition of AF-BC toward the AD microorganisms. Therefore, this study supported practical feasibility of AF-BC-enhanced AD of dairy manure.
Thermal Infrared Evaluation of the Influence of Arbuscular Mycorrhizal Fungus and Dark Septate Endophytic Fungus on Maize Growth and Physiology
Authors: Bi Yinli , Ma Shaopeng , Gao Yakun , Shang Jianxuan , Zhang Yanxu , Xie Linlin , Guo Yun , Christie Peter
Published: April 2022

Thermal infrared imaging technology was used to understand the effects of arbuscular mycorrhizal fungi (AMF) and dark septate endophytic (DSE) fungi, both separately and together, on plant growth and physiological status, and to screen and develop efficient microbial agents in a pot experiment design. Eight treatments comprised the control (CK), AMF inoculation alone, DSE fungal treatments (DSE20%, DSE40% and DSE80%; 2, 4, 8 × 105 CFU mL−1) and combined inoculation treatments (DSE20% + AMF, DSE40% + AMF, and DSE80% + AMF). Canopy temperature (Tcanopy) and stomatal conductance (gs) were monitored at different growth stages, and plant biomass-related indicators were obtained at harvest. These indicators were used to assess plant growth and the physiological status resulting from the different inoculation treatments. During plant growth, the plant Tcanopy decreased following inoculation. Differences in Tcanopy between control and inoculated plants were detected by thermal infrared imaging technology and were −3.8 to + 9.3 °C (control–inoculation treatment). Growth index and Tcanopy monitoring indicate that the growth-promoting effect of combined inoculation was higher than that of either fungal type alone, with DSE80% + AMF producing the highest growth promotion. During the growth process of inoculated maize, the effect of inoculated AMF on the physiological condition of maize growth can be better monitored by thermal infrared at 10 a.m., 12 p.m., 2 p.m. and 4 p.m. on the 31st–57th days of the growth period. The method and results of this experiment are conducive to the rapid and efficient monitoring of the effects of microorganisms on plant growth and physiological status and can be applied to the screening, application, and promotion of microbial agents.
Feeding Calcium-Ammonium Nitrate to Lactating Dairy Goats: Milk Quality and Ruminal Fermentation Responses
Authors: Almeida Kleves V. , Santos Geraldo T. , Osorio Jesus A. C. , Lourenço Jean C. S. , Figueiredo Monique , Durman Thomer , Marchi Francilaine E. , Alcalde Claudete R. , Silva-Junior Ranulfo C. , Itavo Camila C. B. F. , Araujo Rafael C. , Brito Andre F.
Published: April 2022

We aimed to investigate the effects of calcium-ammonium nitrate (CAN) fed to lactating dairy goats on dry matter (DM) intake, digestibility of nutrients, milk properties (composition, antioxidant capacity, fatty acid profile, and nitrate residues), and ruminal fermentation parameters. Twelve lactating Saanen goats averaging 98.5 ± 13.1 days in milk, 53.5 ± 3.3 kg of body weight, and 2.53 ± 0.34 kg of milk/day were randomly assigned in four 3 × 3 Latin squares to receive the following diets: a control group (without CAN) with 7.3 g/kg DM of urea (URE), 10 g/kg DM of CAN (CAN10), and 20 g/kg DM of CAN (CAN20). Each period lasted 21 days, with 14 days for diet adaptation and seven days for data and sample collection. The DM intake, digestibility of nutrients, yields of milk, 3.5% fat-corrected milk, and energy-corrected milk were not affected by treatments. Similarly, there were no treatment effects on the yields and concentrations of milk fat, true protein, and lactose, along with minor effects on milk fatty acid profile. Total antioxidant capacity in milk was unaffected by treatments; however, concentration of conjugated dienes increased, while thiobarbituric acid reactive substances in milk decreased linearly. Nitrate and nitrite residues in milk were elevated by treatments, while the total of volatile fatty acids and ammonia-N concentration in the rumen were unaffected. Collectively, feeding CAN (up to 20 g/kg of DM) to lactating dairy goats did not affect feed intake, nutrient digestibility, and milk composition; however, it may increase milk lipid oxidation, as evidenced by increased conjugated diene concentration.
Dog Owners’ Perspectives on Canine Heart Disease in Klang Valley, Malaysia
Authors: Noordin Norhidayah , Khor Kuan Hua , Khor Kuan Siew , Lim Yi Jun , Lee Yong Chong
Published: April 2022

Canine heart disease often requires long-term treatment, which involves a continuous commitment from the dog owners. In addition to investigating their awareness and knowledge, the Theory of Planned Behavior was applied to also analyze attitude, subjective norm, and perceived behavioral control (PBC) of the dog owners, with empathic concern as a moderator in predicting intention to treat canine heart disease. Through a convenience sampling approach, 261 respondents, who were clients of University Veterinary Hospital, Universiti Putra Malaysia (UVH-UPM), with experience in owning or caring for dogs, were recruited. While the majority of the respondents (83.5%) claimed that they were aware of canine heart disease, most respondents (45.6%) could only identify 5 to 8 (Fair) out of 12 of the salient clinical signs. Most dog owners (92.3%) were willing to seek treatment if the pet dogs were affected, although the intent is deterred by cost (39.5%). In this study, attitude, subjective norms, and perceived behavioral control were significant predictors for the intention to treat. Dog owners with low empathic concern can be motivated to treat affected dogs by cultivating perceived behavioral control. Therefore, continual education may improve dog owners’ preconceived ability to provide care, and veterinarians may play an important role to encourage treatment in dogs diagnosed with heart disease.
Phagocytic Activity, Oxygen Metabolism and Serum Amyloid a Concentration in Peripheral Blood of Mink with Subclinical Aleutian Virus Infection
Authors: Żmuda Andrzej , Lisiecka Urszula , Dudek Katarzyna , Dąbrowski Roman , Gąsiorek Bolesław , Winiarczyk Stanisław , Kostro Krzysztof
Published: April 2022

Aleutian disease (AD) is a chronic disease of mink caused by the Aleutian Mink Disease Virus (AMDV) that results in dysfunction of the immune system. The prevalence of asymptomatic AMDV infections suggests a necessity to explore their effects on the cellular mechanisms of non-specific immunity in farmed mink. The study evaluated the phagocytic activity and oxygen metabolism of peripheral blood granulocytes and monocytes in mink with chronic subclinical AMDV infection. Moreover, the intensity of inflammatory processes was assessed based on the serum amyloid A (SAA) concentration. The analyses involved 24 brown mink females aged 12–24 months. The experimental group (group I) consisted of mink with chronic subclinical AMDV infections, and the control group (group II) included healthy animals. The statistical analysis was performed using the Mann-Whitney U rank test. Phagocytic activity of granulocytes and monocytes was carried out using flow cytometry, and SAA concentration was determined with enzyme-linked immunosorbent assay (ELISA). Compared with the control group, there was a significant decrease in the phagocytic activity and oxygen metabolism of granulocytes and monocytes in the AMDV-infected mink (p < 0.05). Additionally, it was found that the mean SAA value was significantly higher in the group infected with AMDV than in the control group (p < 0.05). The obtained data indicate that monitoring the serum SAA levels in mink with asymptomatic inflammation may help assess the health of mink and detect asymptomatic inflammation caused by AMDV infection.
Reduction in Diarrhoea and Modulation of Intestinal Gene Expression in Pigs Allocated a Low Protein Diet without Medicinal Zinc Oxide Post-Weaning
Authors: Lynegaard Julie C. , Kjeldsen Niels J. , Hansen Christian F. , Williams Andrew R. , Nielsen Jens Peter , Amdi Charlotte
Published: April 2022

Weaning comprises a challenging period for pigs, but dietary tools can be implemented to avoid excess antibiotics usage. Therefore, we tested the effect of a 17.6% crude protein (CP) diet on growth and diarrhoea and investigated the effect of a 15.5% CP diet post-weaning on transcriptomic responses, growth, and diarrhoea-related antibiotic treatments. At weaning, pigs were divided into five dietary treatment groups in a three-phase diet from weaning to 30 kg bodyweight. The diets included a positive control group (PC) with medicinal zinc oxide, a negative control group (NC), a 17.6% CP diet based on soy protein concentrate (SP), a 17.6% CP diet based on soybean meal (SB), and a 15.5% CP diet with additional amino acids (XLA). Growth performance and the occurrence of diarrhoea were similar between the SP and SB groups. The XLA pigs had a reduced weight gain and fewer antibiotics treatments caused by diarrhoea, as well as a reduced level of blood proteins. Intestinal tissue samples from the XLA pigs displayed decreased expression of genes involved in nutrient metabolism and immune responses relative to the PC group. In conclusion, a very low CP diet reduces antibiotics treatments, but also adapts gut nutrient metabolism and reduces growth performance.
High Carriage of Extended-Spectrum, Beta Lactamase-Producing, and Colistin-Resistant Enterobacteriaceae in Tibetan Outpatients with Diarrhea
Authors: Li Zhe , Li Jiaqi , Liu Jiaqi , Peng Yao , Li Zhenpeng , Wang Mengyu , Zhang Ge , Qu Geruo , Zhang Jingyun , Fu Xiuping , Chen Xia , Dunzhu Ciren , Lu Shan , Lu Xin , Xu Jialiang , Kan Biao
Published: April 2022

Antibiotic-resistant bacteria (ARB) and antibiotic-resistance genes (ARGs) have been detected in human-impacted habitats, especially in densely populated cities. The Qinghai–Tibet Plateau is located far from the heavily populated regions of China, and Tibetan residents have distinct dietary habits and gut microbes. Antibiotic-resistance monitoring in the Tibetan population is rare. Here, we collected stool samples from Tibetan outpatients with diarrhea. From 59 samples, 48 antibiotic-resistant Enterobacteriaceae isolates were obtained, including 19 extended-spectrum beta lactamase (ESBL)-producing isolates from 16 patients and 29 polymyxin-resistant isolates from 22 patients. Either ESBL or mcr genes were found in 17 Escherichia coli isolates, approximately 58.8% of which were multidrug-resistant, and ten incompatible plasmid types were found. The gene blaCTX-M was a common genotype in the ESBL-producing E. coli isolates. Four E. coli isolates contained mcr-1. The same mcr-1-carrying plasmid was found in distinct E. coli isolates obtained from the same sample, thus confirming horizontal transmission of mcr-1 between bacteria. Genomic clustering of E. coli isolates obtained from Lhasa, with strains from other regions providing evidence of clone spreading. Our results reveal a strong presence of ARB and ARGs in Tibetan outpatients with diarrhea, implying that ARB and ARGs should be monitored in the Tibetan population.
Glutathione Regulates GPx1 Expression during CA1 Neuronal Death and Clasmatodendrosis in the Rat Hippocampus following Status Epilepticus
Authors: Kim Ji-Eun , Lee Duk-Shin , Kim Tae-Hyun , Kang Tae-Cheon
Published: April 2022

Glutathione peroxidase-1 (GPx1) catalyze the reduction of H2O2 by using glutathione (GSH) as a cofactor. However, the profiles of altered GPx1 expression in response to status epilepticus (SE) have not been fully explored. In the present study, GPx1 expression was transiently decreased in dentate granule cells, while it was temporarily enhanced and subsequently reduced in CA1 neurons following SE. GPx1 expression was also transiently declined in CA1 astrocytes (within the stratum radiatum) following SE. However, it was elevated in reactive CA1 astrocytes, but not in clasmatodendritic CA1 astrocytes, in chronic epilepsy rats. Under physiological condition, L-buthionine sulfoximine (BSO, an inducer of GSH depletion) increased GPx1 expression in CA1 neurons but decreased it in CA1 astrocytes. However, N-acetylcysteine (NAC, an inducer of GSH synthesis) did not influence GPx1 expression in these cell populations. Following SE, BSO aggravated CA1 neuronal death, concomitant with reduced GPx1 expression. Further. BSO also lowered GPx1 expression in CA1 astrocytes. NAC effectively prevented neuronal death and GPx1 downregulation in CA1 neurons, and restored GPx1 expression to the control level in CA1 astrocytes. In chronic epilepsy rats, BSO reduced GPx1 intensity and exacerbated clasmatodendritic degeneration in CA1 astrocytes. In contrast, NAC restored GPx1 expression in clasmatodendritic astrocytes and ameliorated this autophagic astroglial death. To the best of our knowledge, our findings report, for the first time, the spatiotemporal profiles of altered GPx1 expression in the rat hippocampus following SE, and suggest GSH-mediated GPx1 regulation, which may affect SE-induced neuronal death and autophagic astroglial degeneration.
NRF2 Alters Mitochondrial Gene Expression in Neonate Mice Exposed to Hyperoxia
Authors: Vellers Heather L. , Cho Hye-Youn , Gladwell Wesley , Gerrish Kevin , Santos Janine H. , Ofman Gaston , Miller-DeGraff Laura , Mahler T. Beth , Kleeberger Steven R.
Published: April 2022

Approximately 1 in 10 newborns are born preterm and require supplemental oxygen (O2) in an extrauterine environment following birth. Supplemental O2 can induce oxidative stress that can impair mitochondrial function, resulting in lung injury and increased risk in early life pulmonary diseases. The nuclear factor-erythroid 2 related factor 2 (NRF2) protects the cells from oxidative stress by regulating the expression of genes containing antioxidant response elements and many mitochondrial-associated genes. In this study, we compared Nrf2-deficient (Nrf2−/−) and wild-type (Nrf2+/+) mice to define the role of NRF2 in lung mitochondrial genomic features in late embryonic development in mice (embryonic days, E13.5 and E18.5) versus birth (postnatal day 0, PND0). We also determined whether NRF2 protects lung mitochondrial genome parameters in postnatal mice exposed to a 72 h hyperoxia environment. We found Nrf2−/− embryonic lungs were characterized by decreases in mtDNA copies from E13.5 to E18.5. Interestingly, Nrf2−/− heteroplasmy frequency was significantly higher than Nrf2+/+ at E18.5, though this effect reversed at PND0. In postnatal mice exposed to hyperoxia, we identified three- to four-fold increases in mitochondria-encoded mitochondrial genes, which regulate oxidative phosphorylation. Overall, our findings demonstrate a potentially critical role of NRF2 in mediating long-term effects of hyperoxia on mitochondrial function.
Organ-on-a-Chip: Design and Simulation of Various Microfluidic Channel Geometries for the Influence of Fluid Dynamic Parameters
Authors: Pisapia Francesca , Balachandran Wamadeva , Rasekh Manoochehr
Published: April 2022

Shear stress, pressure, and flow rate are fluid dynamic parameters that can lead to changes in the morphology, proliferation, function, and survival of many cell types and have a determinant impact on tissue function and viability. Microfluidic devices are promising tools to investigate these parameters and fluid behaviour within different microchannel geometries. This study discusses and analyses different designed microfluidic channel geometries regarding the influence of fluid dynamic parameters on their microenvironment at specified fluidic parameters. The results demonstrate that in the circular microchamber, the velocity and shear stress profiles assume a parabolic shape with a maximum velocity occurring in the centre of the chamber and a minimum velocity at the walls. The longitudinal microchannel shows a uniform velocity and shear stress profile throughout the microchannel. Simulation studies for the two geometries with three parallel microchannels showed that in proximity to the micropillars, the velocity and shear stress profiles decreased. Moreover, the pressure is inversely proportional to the width and directly proportional to the flow rate within the microfluidic channels. The simulations showed that the velocity and wall shear stress indicated different values at different flow rates. It was also found that the width and height of the microfluidic channels could affect both velocity and shear stress profiles, contributing to the control of shear stress. The study has demonstrated strategies to predict and control the effects of these forces and the potential as an alternative to conventional cell culture as well as to recapitulate the cell- and organ-specific microenvironment.
How the Direction of Screws Affects the Primary Stability of a Posterior Malleolus Osteosynthesis under Torsional Loading: A Biomechanical Study
Authors: Kohler Felix Christian , Schenk Philipp , Koehler Paul , Wildemann Britt , Hofmann Gunther Olaf , Derlien Steffen , Biedermann Uta , Graul Isabel , Hallbauer Jakob
Published: April 2022

Insufficient fixation of a posterior malleolus fracture (PM) can lead to posttraumatic complications such as osteoarthritis and chronic pain. The purpose of this biomechanical study was to test the hypothesis of whether the direction of PM screw fixation has an impact on the primary stability of osteosynthesis of a PM under torsional loading. PM fractures of 7 pairs human cadaveric lower leg specimens were stabilized with posterior to anterior (p.a.) or anterior to posterior (a.p.) screw fixation. Stability of the osteosynthesis was biomechanically tested using cyclic external torsional loading levels, in 2 Nm steps from 2 Nm up to 12 Nm, under constant monitoring with 3D ultrasonic marker (Zebris). The primary stability does not differ between both stabilizations (p = 0.378) with a medium effect size (η2p = 0.065). The movement of the PM tends to be marginally greater for the osteosynthesis with a.p. screws than with p.a. screws. Whether a.p. screws or the alternative p.a. screw fixation is performed does not seem to have an influence on the primary stability of the osteosynthesis of the PM fixation under torsional loading. Although osteosynthesis from posterior seems to be more stable, the biomechanical results in the torsional test show quite equivalent stabilities. If there is no significant dislocation of the PM, a.p. screw fixation could be a minimally invasive but stable surgical strategy.
Traditional Grain-Based vs. Commercial Milk Kefirs, How Different Are They?
Authors: Nejati Fatemeh , Capitain Charlotte C. , Krause Jannike Lea , Kang Gi-Ung , Riedel René , Chang Hyun-Dong , Kurreck Jens , Junne Stefan , Weller Philipp , Neubauer Peter
Published: April 2022

Traditional kefir, which is claimed for health-promoting properties, is made from natural grain-based kefir, while commercial kefirs are made of defined mixtures of microorganisms. Here, approaches are described how to discriminate commercial and traditional kefirs. These two groups of kefirs were characterized by in-depth analysis on the taxonomic and functional level. Cultivation-independent targeted qPCR as well as next-generation sequencing (NGS) proved a completely different microbial composition in traditional and commercial kefirs. While in the traditional kefirs, Lactobacillus kefiranofaciens was the dominant bacterial species, commercial kefirs were dominated by Lactococcus lactis. Volatile organic compounds (VOCs) analysis using headspace-gas chromatography-ion mobility spectrometry also revealed drastic differences between commercial and traditional kefirs; the former built a separate cluster together with yogurt samples. Lactose and galactose concentrations in commercial kefirs were considerably higher than in traditional kefirs, which is important regarding their health properties for people who have specific intolerances. In summary, the analyzed commercial kefirs do not resemble the microbial community and metabolite characteristics of traditional grain-based kefir. Thus, they may deliver different functional effects to the consumers, which remain to be examined in future studies.
Quasi-Isotropic Hybrid Dielectric Resonator Antenna—Bow-Tie Patch with Harmonic Suppression
Authors: Jeong Taeyong , Lee Jong Seon , Lee Dong Geun , Kim Jun Hee , Park Jinsu , Hwang Dong Hyee , Hwang Keum Cheol
Published: April 2022

This paper proposes a quasi-isotropic hybrid dielectric resonator antenna (DRA) and bow-tie patch with harmonics suppression. The suggested antenna consists of a DRA, a bow-tie patch, and a microstrip seventh-order Chebyshev low-pass filter. By loading a bow-tie patch on the designed DRA, a quasi-isotropic pattern is realized. The seventh-order Chebyshev low-pass filter was applied to the feed line, and harmonics were reduced in the section separate to the operating band to remove harmonics generated by the proposed antenna. The simulated S11 that satisfies below −10 dB is 3.09–3.3 GHz (6.25%), and the measured S11 is 3.10–3.28 GHz (5.64%). The simulated gain difference considering all radiating regions (0∘≤φ≤360∘ and 0∘≤θ≤180∘) is 7.211 dB. Compared with the antenna without a filter, the harmonic gain was reduced by 10.847 and 15.774 dB. The measured gain isolation of the operating band and the second and third harmonics are 10.10 and 18.94 dB, respectively. The proposed antenna is considered to be applicable to applications that require radio wave reception in all directions such as wireless point access points, internet of things and radio frequency identification, and is expected to contribute to reducing the size of the RF system.
Attention Map-Guided Visual Explanations for Deep Neural Networks
Authors: An Junkang , Joe Inwhee
Published: April 2022

Deep neural network models perform well in a variety of domains, such as computer vision, recommender systems, natural language processing, and defect detection. In contrast, in areas such as healthcare, finance, and defense, deep neural network models, due to their lack of explainability, are not trusted by users. In this paper, we focus on attention-map-guided visual explanations for deep neural networks. We employ an attention mechanism to find the most important region of an input image. The Grad-CAM method is used to extract the feature map for deep neural networks, and then the attention mechanism is used to extract the high-level attention maps. The attention map, which highlights the important region in the image for the target class, can be seen as a visual explanation of a deep neural network. We evaluate our method using two common metrics: average drop and percentage increase. For a more effective experiment, we also propose a new metric to evaluate our method. The experiments were carried out to show that the proposed method works better than the state-of-the-art explainable artificial intelligence method. Our approach can provide a lower average drop and higher percent increase when compared to other methods and find a more explanatory region, especially in the first twenty percent region of the input image.
Expanding the Sediment Transport Tracking Possibilities in a River Basin through the Development of a Digital Platform—DNS/SWAT
Authors: Wilk Paweł
Published: April 2022

Simulation of stochastic and variable sediment transport processes within models still poses a big challenge, especially in mountainous areas. Since sediment transport, including erosion and deposition, remains an unceasing problem in many areas, sediment modeling is perceived as a possible solution. This article combines a review of the selected sediment models with a presentation of the effects of several years of research using the DNS digital platform in the Western Carpathians. The review focuses on the main advantages and gaps in selected modeling tools with particular emphasis on one of the most popular: SWAT. The description of the digital platform—DNS is an example of how to answer these gaps by combining subsequent models, methods, and databases using their best features. To accentuate the benefits of such an approach, the effects of combining subsequent models (AdH/PTM) and methods (fingerprinting) on a common digital DNS space are presented, on the example of the Raba River (basin). In this way, both unique possibilities of estimating the amount of contamination carried with sediment particles and their sources, as well as sequencing of sedimentation in the reservoir, taking into account its subsequent zones, were obtained.
Theoretical Feasibility Analysis of Fast Back-Projection Algorithm for Moon-Based SAR in Time Domain
Authors: Chen Guoqiang , Guo Huadong , Liang Da , Han Chunming , Ding Yixing , Jiang Huiping , Zhang Ke
Published: April 2022

Nowadays, the Earth observation based on the Moon has attracted attention from many researchers and relevant departments. There also exists a considerable amount of interest in monitoring large-scale and long-term geoscience phenomena using the Moon-based SAR (MBS). However, the Earth’s observation from MBS has long transmission time, and the relative motion of MBS with its Earth ground target (EGT) is much different to the space-borne SAR, the above reasons indicate that the traditional stop-and-go model is no longer suitable for MBS in frequency domain imaging. Here a dual-path separate calculation method for single pulse is presented in this paper for a better match of a real scenario, and then the slant range is fitted to a high-order polynomial series. The MBS’s location, the synthetic aperture time and other factors have effects on length of the dual- path and fit bias. Without thoroughly investigated phase de-correlation processing in frequency domain, and to avoid computational costs in traditional back-projection (BP) algorithm, the paper first proposes a fast back-projection (FBP) algorithm in time domain for MBS, a platform that has long transmission time and long synthetic aperture time. In the FBP algorithm, the original method, that projected echo on all pixels in the imaging area, is changed to projected echo on a centerline instead. A suitable interpolation for points on the centerline is adopted to reduce the projected error; the synthetic aperture length and imaging area are also divided into subsections to reduce computation cost. The formula indicates that the range error could be control once the product of sub-imaging area’s length and sub-aperture’s length stay constant. Through the theoretical analysis, the detailed range difference mainly at apogee, perigee, ascending, and descending nodes indicate the necessity to separately calculate the dual-path for MBS’s single pulse transmission in Earth-Moon motion, with real ephemeris been adopted; then, the high-order polynomial fitting will better describe the motion trajectory. Lastly, the FBP algorithm proposed is simulated in a specific scenario under acceptable resolution, and the result shows its feasibility for image compression.
A Novel Hybrid Model for the Prediction and Classification of Rolling Bearing Condition
Authors: Wang Aina , Li Yingshun , Yao Zhao , Zhong Chongquan , Xue Bin , Guo Zhannan
Published: April 2022

Rotating machinery is a key piece of equipment for tremendous engineering operations. Vibration analysis is a powerful tool for monitoring the condition of rotating machinery. Furthermore, vibration signals have the characteristics of time series. Hence, it is necessary to monitor the condition of vibration signal series to avoid any catastrophic failure. To this end, this paper proposes an effective condition monitoring strategy under a hybrid method framework. First, we add variational mode decomposition (VMD) to preprocess the data points listed in a time order into a subseries, namely intrinsic mode functions (IMFs). Then the framework of the hybrid prediction model, namely the autoregressive moving average (ARMA)-artificial neural network (ANN), is adopted to forecast the IMF series. Next, we select the sensitive modes that contain the prime information of the original signal and that can imply the condition of the machinery. Subsequently, we apply the support vector machine (SVM) classification model to identify the multiple condition patterns based on the multi-domain features extracted from sensitive modes. Finally, the vibration signals from the Case Western Reserve University (CWRU) laboratory are utilized to verify the effectiveness of our proposed method. The comparison results demonstrate advantages in prediction and condition monitoring.
Location Planning of Charging Stations for Electric Buses in Public Transport Considering Vehicle Scheduling: A Variable Neighborhood Search Based Approach
Authors: Olsen Nils , Kliewer Natalia
Published: April 2022

Many public transport companies have recently launched projects testing the operation of electric buses. Progressively, traditional combustion engine buses are being replaced by electric buses. In such cases, some stops on bus lines are equipped with charging technology. Combustion engine buses can operate for an entire day without having to refuel. By contrast, electric buses have considerably shorter ranges and need to recharge their batteries throughout a day. For cost-efficient use of electric buses, charging stations must be located within the road network so that required deadhead trips are as short as possible, but attention must also be paid to construction costs. In contrast to vehicle scheduling, which is a more short-term planning task of public transport companies, location planning of charging stations is a long-term planning problem and requires a simultaneous solving of both optimization problems. Specifically, location planning and vehicle scheduling have to be considered simultaneously in order to open up optimization potentials by comparison to sequential planning, since locations of charging stations directly influence the resulting vehicle rotations. To this purpose, we present a novel solution method for the simultaneous optimization of location planning of charging stations and vehicle scheduling for electric buses in public transport, using variable neighborhood search. By a computational study using real-world public transport data, we show that a simultaneous consideration of both problems is necessary because sequential planning generally leads to either infeasible vehicle rotations or to significant increases in costs. This is especially relevant for public transport companies that start operating electric bus fleets.
Analysis of Uncertainties in Clinical High-Energy Photon Beam Calibrations Using Absorbed Dose Standards
Authors: Elbashir Fawzia E. M. , Ksouri Wassim , Habbani Farouk , El-Khayatt Ahmed M. , Eisa Mohamed Hassan , Suliman Ibrahim I.
Published: April 2022

We compared the results of absorbed dose measurements made using the TRS-398, TG-51, and DIN protocols and their associated uncertainties to reduce discrepancies in measurement results made using the three protocols. This experiment was carried out on two Varian Medical linear accelerators with 4, 6, 10, and 20 MV photon energies using FC65-G and CC15 (cylindrical) and NACP-02-type (plane-parallel) ion chambers in water phantoms. The radiation beam quality index (Q) was determined from the measurement of percentage depth dose. It was used to determine the photon beam quality factor required with the ionization chamber calibration factor to convert the ion chamber reading into the absorbed dose to water. For the same beam quality, the TRS-398/TG-51 varied from 0.01% to 1.8%, whereas the ratio for TRS-398/DIN 6800-2 varied from 0.1% to 0.88%. The chamber-to-chamber variation was 0.09% in TRS-398/TG-51, 0.03% in TRS-398/DIN, and 0.02% in TG-51/DIN 6800-2. The expanded uncertainties (k = 1) were 1.24 and 1.25 when using TRS-398 and DIN 6800-2, respectively. Using the aforementioned three protocols, the results showed little chamber-to-chamber variation and uncertainty in absorbed dose measurements. The estimated uncertainties when using cylindrical ion chambers were slightly lower than those measured using plane-parallel chambers. The results are important in facilitating comparisons of absorbed dose measurements when using the three protocols.
Effect of the Preheating Strategy on the Combustion Process of the Intake Manifold Burner
Authors: Li Zhishuang , Wang Ziman , Mo Haoyang
Published: April 2022

The intake air preheating is an effective method to improve the cold start performance of diesel engines. The combustion process and ignition probability were investigated in the present study. The average flame area (AFA) during the steady stage of the combustion process was used to evaluate the effects of various factors on combustion. The increase of voltage was found to enhance the combustion process, while the increased diesel flow rate first promoted the combustion before deteriorating it. The increased intake air flow velocity enhanced the combustion within 2.64 m/s, and excessive air flow velocity hindered the combustion from 2.7 to 3 m/s. The cross-distributed vortex clusters in the combustion chamber, periodic diesel evaporation and vortexes with opposite rotation directions in the vicinity of the intake manifold burner were believed to be the main reasons for flame stripping and swirl motion. The temperature rise in the exhaust pipe was recorded to investigate the thermal distribution. The warm air was concentrated in the upper region because of the buoyancy effect of the flame. With the air flow velocity increasing from 1.4 to 10 m/s, the average temperature rise increased first before decreasing, while the combustion efficiency increased due to the increased air flow volume.
Computational Study of Inertial Flows in Helical Microchannels
Authors: Ďuračíková Kristína Kovalčíková , Cimrák Ivan
Published: April 2022

The sorting of biological cells or particles immersed in a fluid is a frequent goal in the domain of microfluidics. One approach for such sorting is in using the inertial effects that are present in curved channels. In this study, we propose a new approach of inertial focusing of cells in microfluidic devices. The investigated channels had the form of a helical channel with a circular cross-section, and the cells were spherical. We identified the key parameters that influence the cell sorting results through multiple computational simulations using a modelling tool PyOIF within the package ESPResSo. We found that spherical cells could be sorted with respect to their size in helical channels since their stabilised positions are located in different parts of the channel cross section. The location of the stabilised position is a function of the fluid parameters, the geometrical parameters of the helical device, and the size of the immersed cells.
Numerical Simulation Study of Brittle Rock Materials from Micro to Macro Scales Using Digital Image Processing and Parallel Computing
Authors: Liu Xin , Liang Zhengzhao , Meng Siwei , Tang Chunan , Tao Jiaping
Published: April 2022

The multi-scale, high-resolution and accurate structural modeling of rocks is a powerful means to reveal the complex failure mechanisms of rocks and evaluate rock engineering safety. Due to the non-uniformity and opacity of rocks, describing their internal microstructure, mesostructure and macro joints accurately, and how to model their progressive fracture process, is a significant challenge. This paper aims to build a numerical method that can take into account real spatial structures of rocks and be applied to the study of crack propagation and failure in different scales of rocks. By combining the failure process analysis (RFPA) simulator with digital image processing technology, large-scale finite element models of multi-scale rocks, considering microstructure, mesostructure, and macro joints, were created to study mechanical and fracture behaviors on a cloud computing platform. The Windows-Linux interactive method was used for digital image processing and parallel computing. The simulation results show that the combination of a parallel RFPA solver and digital image modeling technology can achieve high-resolution structural modeling and high-efficiency calculation. In microscopic simulations, the influence of shale fractures and mineral spatial distribution on the fracture formation process can be revealed. In the mesostructure simulation, it can be seen that the spatial distribution of minerals has an impact on the splitting mode of the Brazilian splitting model. In the simulation of a joined rock mass, the progressive failure process can be effectively simulated. According to the results, it seems that the finite element parallel computing simulation method based on digital images can simulate the multi-scale failure process of brittle materials from micro to macro scales. Primarily, efficient parallel computing based on a cloud platform allows for the multi-scale, high-resolution and realistic modeling and analysis of rock materials.
A Deterministic Methodology Using Smart Card Data for Prediction of Ridership on Public Transport
Authors: Lee Minhyuck , Jeon Inwoo , Jun Chulmin
Published: April 2022

In the present study, we propose a methodology that predicts the number of passengers on new public transport lines based on smart card data and an optimal path finding algorithm. It employs a deterministic approach that assumes that, when a new line is added to the public transport network, passengers choose the fastest route to their destination. The proposed methodology is applied to actual lines (bus and subway lines) in Seoul, the capital of South Korea, and it is validated through the observed traffic volume of those lines recorded in the smart card data. The experiments are conducted using smart card data, with more than 100 million trips stored, extracted from about 1 million passengers who have check-in records in the catchment area of the new lines. The experimental results show that the proposed methodology predicts the daily average number of passengers very similar to the observed data.
Maximum Safe Parameters of Outbound Loaded Vessels for Wind Turbine Installation
Authors: Gucma Stanisław , Gralak Rafał , Przywarty Marcin , Ślączka Wojciech
Published: April 2022

A paper presents problems related to the safe operation of wind turbine installation vessels in port waterways. It presents a developed method for determining maximum safe lengths of blades of wind turbines loaded transversely on a jack-up vessel leaving a given port. In this method, the safety criterion for navigation is the acceptable risk of accidents, whose scenarios are determined by the identification of hazards in the studied waterway. Based on this safety criterion, the confidence level of the width of the safe maneuvering area of the loaded jack-up vessel and the maximum safe lengths of the transversely loaded wind turbine blades, respectively, are determined.
An Experimental Study on the Migration of Pb in the Groundwater Table Fluctuation Zone
Authors: Qu Jihong , Yan Tiangang , Zhang Yifeng , Li Yuepeng , Tian Ran , Guo Wei , Jiang Jueyan
Published: April 2022

As a result of fluctuations in the shallow groundwater table, hydrodynamic conditions change alongside environmental conditions and hydrogeochemical processes to affect pollutant migration. The study aimed to investigate the migration, adsorption, and desorption characteristics of Pb on fine, medium, and coarse sand in the water table fluctuation zone by using several laboratory methods, including the kinetic aspects of Pb2+ adsorption/desorption and water table fluctuation experiments. The results showed that the adsorption and desorption curves fit the Elovich equation well at a correlation coefficient above 0.9. In the adsorption and desorption kinetic experiments for fine, medium, and coarse sand collected and from the floodplain, the maximum adsorption capacity of Pb2+ was 2367 mg·kg−1, 1848 mg·kg−1, and 1544 mg·kg−1, respectively. The maximum desorption capacity of Pb2+ was 29.18 mg·kg−1, 62.38 mg·kg−1, and 81.60 mg·kg−1, respectively. In environments with pH greater than 4, the adsorption capacity was proportional to the pH, but the desorption capacity decreased as the pH increased in water. As the water table varied, the lowest pH occurred in the polluted medium we set initially. When the distance between the pollutants and sample solution grew further, pH increased, and the Pb2+ concentration decreased in the sample solution. In the column experiment of water table fluctuations on coarse sand, Pb2+ migrated nearly 5 cm upward from the original pollutant and migrated less than 10 cm downward from that. In our experiments on medium and fine sand, the upward and downward migration distances were <5 cm. The groundwater table fluctuations, pH variation, and Pb concentration currently influence the migration of Pb.
Assessing Spatial Variation of PBL Height and Aerosol Layer Aloft in São Paulo Megacity Using Simultaneously Two Lidar during Winter 2019
Authors: Moreira Gregori de Arruda , Oliveira Amauri Pereira de , Codato Georgia , Sánchez Maciel Piñero , Tito Janet Valdés , Silva Leonardo Alberto Hussni e , Silveira Lucas Cardoso da , Silva Jonatan João da , Lopes Fábio Juliano da Silva , Landulfo Eduardo
Published: April 2022

This work presents the use of two elastic lidar systems to assess the horizontal variation of the PBL height (PBLH) and aerosol layer aloft in the São Paulo Megacity. These two lidars performed simultaneous measurements 10.7 km apart in a highly urbanized and relatively flat area of São Paulo for two winter months of 2019. The results showed that the PBLH differences display diurnal variation that depends on the PBL during daytime growth phases. Cloud and sea breeze effects control most of PBLH variation. In the absence of cloud and sea breeze, the maximum difference (~300 m) occurs in the rapid development stage and is due to topographic effects. When the PBL approaches its maximum daily value, it tends to level off with respect to the topography. In addition, it was presented a method that combines elastic lidar (to detect an aerosol layer) and satellite data (to classify such a layer from Aerosol Optical Depth (AOD) and Aerosol Index (AI) information) for the detection of biomass burning events. This methodology demonstrated that the variations caused by Biomass Burning in AOD and AI enable both the detection of aerosol plumes originating from biomass burning and the identification of their origin.