bluuebunny/crossref_metadata_2025 huggingface dataset:
Public Acceptance of Renewable Energy Sources: a Case Study from the Czech Republic
Authors: Čábelková Inna , Strielkowski Wadim , Firsova Irina , Korovushkina Marina
Published: April 2020

The substitution of traditional energy production with renewable energy sources (RES) in the European Union (EU) represents a multidimensional issue with its pros and cons viewed differently by governments, technology companies, markets, as well as the general public. There are significant public doubts in expediency of investments in renewables in place. Our paper studies the factors related to the public opinion on renewables using a reasonable and representative sample of respondents (N = 1026) from one of the EU Member States, the Czech Republic, via a set of ordinal regression analyses with spline correction for ordinal predictors. Our results suggest that the population of the Czech Republic is split in half in its trust in renewables as a substitute to traditional energy sources. In addition, our results show that the opinions on renewables in the Czech Republic are significantly related to personal concerns on environmental protection and worries about use of nuclear energy. Moreover, we find that traditional mass media is not statistically significant, even though internet news channels and social media were statistically related to the opinions (negatively and positively, respectively). The comparison of the responses with respect to the frequency of following social media support the hypothesis of the media bubble. The empirical results indicate that public opinions on renewables are likely to be built on the information sources vulnerable to hoaxes, bubbles, and misinformation. We conclude that more media presentation on RES is needed and make some practical suggestions for the stakeholders, journalists, and relevant policymakers.
Numerical Study of the Normal Impinging Water Jet at Different Impinging Height, Based on Wray–Agarwal Turbulence Model
Authors: Wang Hongliang , Qian Zhongdong , Zhang Di , Wang Tao , Wang Chuan
Published: April 2020

As a kind of water jet technology with strong impinging force and simple structure, the submerged impinging water jet can produce strong scouring action on subaqueous sediments. In order to investigate the flow field characteristics and impinging pressure of submerged impinging water jets at different impinging heights, the Wray-Agarwal (W-A) turbulence model is used for calculation. The velocity distribution and flow field structure at different impinging heights (1 ≤ H/D ≤ 8), and the impinging pressure distribution at the impingement plate under different Reynolds numbers (11, 700 ≤ Re ≤ 35100) are studied. The results show that with the increase of the impinging height, the diffusion degree increases and the velocity decreases gradually when the jet reaches the impingement region. The fluid accelerates first and then decelerates near the stagnation point. The maximum impinging pressure and the impinging pressure coefficient decrease with the increase of the impinging height, but the effective impinging pressure range remains unchanged. In this paper, the distribution characteristics of the impinging pressure in the region of the impingement plate at different heights are clarified, which provides theoretical support for the prediction method of the impinging pressure.
Neuro-Fuzzy System for Energy Management of Conventional Autonomous Vehicles
Authors: Phan Duong , Bab-Hadiashar Alireza , Hoseinnezhad Reza , N. Jazar Reza , Date Abhijit , Jamali Ali , Pham Dinh Ba , Khayyam Hamid
Published: April 2020

This paper investigates the energy management system (EMS) of a conventional autonomous vehicle, with a view to enhance its powertrain efficiency. The designed EMS includes two neuro-fuzzy (NF) systems to produce the optimal torque of the engine. This control system uses the dynamic road power demand of the autonomous vehicle as an input, and a PID controller to regulate the air mass flow rate into the cylinder by changing the throttle angle. Two NF systems were trained by the Grid Partition (GP) and the Subtractive Clustering (SC) methods. The simulation results show that the proposed EMS can reduce the fuel consumption of the vehicle by 6.69 and 6.35 l/100 km using the SC and the GP, respectively. In addition, the EMS based on NF trained by GP and NF trained by SC can reduce the fuel consumption of the vehicle by 11.8% and 7.08% compared with the case without the controller, respectively.
Experimental Validation of a Heat Transfer Model in Underground Power Cable Systems
Authors: Ocłoń Paweł , Pobędza Janusz , Walczak Paweł , Cisek Piotr , Vallati Andrea
Published: April 2020

This paper presents the laboratory test stand that is used for experimental validation of underground power cable system models. Determination of temperature distribution in the vicinity of the cable is the main goal of the study. The paper considers a system of three power cables, situated in the in-line arrangement, and buried in sand. Three electrical heaters of special construction are used in order to simulate the heat flux that is generated in the power cables during their operation. The test stand is designed to be placed in a thermoclimatic chamber, which allows testing the system in various thermal conditions when the ambient temperature changes by 20 °C to 30 °C. Numerical computations of the steady-state temperature fields are performed using the finite element method.
3D Spatial Reuse of Multi-Millimeter-Wave Spectra by Ultra-Dense In-Building Small Cells for Spectral and Energy Efficiencies of Future 6G Mobile Networks
Authors: Saha Rony Kumer
Published: April 2020

The sixth-generation (6G) mobile networks are expected to operate at a higher frequency to achieve a wider bandwidth and to enhance the frequency reuse efficiency for improved spectrum utilization. In this regard, three-dimensional (3D) spatial reuse of millimeter-wave (mmWave) spectra by in-building small cells is considered an effective technique. In contrast to previous works exploiting microwave spectra, in this paper, we present a technique for the 3D spatial reuse of 28 and 60 GHz mmWave spectra by in-building small cells, each enabled with dual transceivers operating at 28 and 60 GHz bands, to enhance frequency reuse efficiency and achieve the expected spectral efficiency (SE) and energy efficiency (EE) requirements for 6G mobile networks. In doing so, we first present an analytical model for the 28 GHz mmWave spectrum to characterize co-channel interference (CCI) and deduce a minimum distance between co-channel small cells at both intra- and inter-floor levels in a multistory building. Using minimum distances at both intra- and inter-floor levels, we find the optimal 3D cluster size for small cells and define the corresponding 3D spatial reuse factor, such that the entire 28 and 60 GHz spectra can be reused by each 3D cluster in each building. Considering a system architecture where outdoor macrocells and picocells operate in the 2 GHz microwave spectrum, we derive system-level average capacity, SE, and EE values, as well as develop an algorithm for the proposed technique. With extensive numerical and simulation results, we show the impacts of 3D spatial reuse of multi-mmWave spectra by small cells in each building and the number of buildings per macrocell on the average SE and EE performances. Finally, it is shown that the proposed technique can satisfy the expected average SE and EE requirements for 6G mobile networks.
Measurement and Verification of Integrated Ground Source Heat Pumps on a Shared Ground Loop
Authors: Shin Jeong Soo , Park Jong Woo , Kim Sean Hay
Published: April 2020

We propose an integrated geothermal system that consists of air-conditioning and hot water service ground source heat pumps, both of which share a ground water loop. The proposed system increases the COP of the service hot water ground source heat pump by recovering the condensation heat of the air-conditioning ground source heat pump as an evaporator heat source for the hot water service ground source heat pump. Eventually this integration expands the scope and capacity of the evaporator source in addition to the underground water of heat exchangers, which also leads to increase the COP of the air-conditioning ground source heat pump. The integrated geothermal heat pump system was installed in a hotel, and then data were measured for a limited period due to the hotel’s ongoing business activities. A TRNSYS simulation model has been developed as a baseline, and the baseline has been calibrated with the measured data. By running one-year simulations, it turns out that the annual electricity use for heating and cooling, and service hot water was reduced by 19.1% in the cooling season, and by 9.6% in the heating season, with respect to the conventional configuration in which the air-conditioning heat pump and hot water service heat pump work individually on their own ground loops.
Simulation Test of a DC Fault Current Limiter for Fault Ride-Through Problem of Low-Voltage DC Distribution
Authors: Han Bing , Li Yonggang
Published: April 2020

The low voltage direct current (LVDC) distribution networks are connected with too many kinds of loads and sources, which makes them prone to failure. Due to the small damping value in the DC lines, the fault signal propagates so fast that the impact current with the wave front of millisecond and the transient voltage pose great challenges for fault detection. Even worse, some faults with small currents are difficult to detect and the communication is out of sync, resulting in protection misoperation. These problems have severely affected the new energy utilization. In view of this, a DC fault current limiter (FCL) composed of inductance, resistance, and power electronic switch was designed in this paper. The rising speed of fault current can be decreased by the series inductance and the peak value of the fault current can be limited by series impedance, thus in this way the running time can be gained for fault detection and protection. For distributed energy access, by deducing the short circuit fault characteristic expression of LVDC distribution network, the feasibility of FCL was verified. Based on the structure of the bridge-type alternating current (AC) current limiter, the structure and parameters of the DC FCL were determined according to the fault ride-through target. Then, a low voltage ride-through strategy based on DC FCL was proposed for the bipolar short-circuit fault of LVDC distribution network. Finally, MATLAB/Simulink simulation was used to verify the rationality of the proposed FCL and its ride-through strategy.
The Potential of RES in the Reduction of Air Pollution: The SWOT Analysis of Smart Energy Management Solutions for Krakow Functional Area (KrOF)
Authors: Jeleński Tomasz , Dendys Marta , Tomaszewska Barbara , Pająk Leszek
Published: April 2020

Health impacts and a decrease in the quality of life caused by air pollution is a major problem worldwide. Krakow is one of the most affected cities in the EU by air pollution mostly caused by burning solid fuels in households’ furnaces. It is considered that the most effective remedies would be adequate spatial planning solutions and application of low-emission sources including renewable energy sources (RES). This article draws from the analysis of the use of RES as a means for reducing harmful emissions in Krakow Functional Area (KrOF). The inventories of renewable energy sources and systems were compiled by the authors as a part of the EU project “Smart Edge—Sustainable Metropolitan Areas and the Role of The Edge City”. Using the data from the inventories, a SWOT analysis has been carried out to identify factors that determine the smart management of the RES potential, particularly the decisions of households on the transition towards RES. The results of the analysis have shown that many actions have been taken at the national, regional, and local levels but the greatest influence bear the solutions initiated and implemented at the communal level. The conclusion is that legislative regulations should be combined with locally tailor-made instruments. The proposed method of analysis can be applied in other metropolitan areas as a diagnostic procedure supporting action planning to solve air-quality problems caused by distributed emission sources.
Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic
Authors: Crnogorac Miroslav , Tanasijević Miloš , Danilović Dušan , Karović Maričić Vesna , Leković Branko
Published: April 2020

Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based on empirical data from the selected oil fields. Results are presented in two ways: according to the surfaces of irregular geometric bodies, and their gravity with the scattering of results, i.e., on smaller and greater possibilities of interpreting results when there are small differences in outputs. Finally, a sensitivity analysis of the model is presented.
Regional Variability of the Romanian Main Tree Species Growth Using National Forest Inventory Increment Cores
Authors: Marin Gheorghe , Strimbu Vlad C. , Abrudan Ioan V. , Strimbu Bogdan M.
Published: April 2020

In many countries, National Forest Inventory (NFI) data is used to assess the variability of forest growth across the country. The identification of areas with similar growths provides the foundation for development of regional models. The objective of the present study is to identify areas with similar diameter and basal area growth using increment cores acquired by the NFI for the three main Romanian species: Norway spruce (Picea abies L. Karst), European beech (Fagus sylvatica L.), and Sessile oak (Quercus petraea (Matt.) Liebl.). We used 6536 increment cores with ages less than 100 years, a total of 427,635 rings. The country was divided in 21 non-overlapping ecoregions based on geomorphology, soil, geology and spatial contiguousness. Mixed models and multivariate analyses were used to assess the differences in annual dimeter at breast height and basal area growth among ecoregions. Irrespective of the species, the mixed models analysis revealed significant differences in growth between the ecoregions. However, some ecoregions were similar in terms of growth and could be aggregated. Multivariate analysis reinforced the difference between ecoregions and showed no temporal grouping for spruce and beech. Sessile oak growth was separated not only by ecoregions, but also by time, with some ecoregions being more prone to draught. Our study showed that countries of median size, such as Romania, could exhibit significant spatial differences in forest growth. Therefore, countrywide growth models incorporate too much variability to be considered operationally feasible. Furthermore, it is difficult to justify the current growth and yield models as a legal binding planning tool.
Drivers of Consumer Liking for Beef, Pork, and Lamb: A Review
Authors: Miller Rhonda
Published: April 2020

Tenderness, juiciness, and flavor have been associated with consumer acceptance of beef, lamb, and pork. Drivers of consumer liking are interrelated across these species, but there are differences in consumer preferences. Animal age, animal diet, and subsequent marbling impact consumer liking across species. For beef, consumer research prior to the 1990s showed that tenderness was the main driver of liking. Consumer tenderness and juiciness liking are highly correlated. More recent research has shown that as overall tenderness improved and tenderness variation decreased, flavor has become a more important driver of beef consumer liking. Flavor is affected by consumer preparation methods, familiarity with different flavor presentations, and animal production systems. Animal diet impacts consumer perception of beef tenderness and flavor, especially when comparing forage-fed versus grain-fed beef. Flavor preferences vary across countries more so than preferences for beef based on consumer tenderness preferences and are most likely influenced by the consumption of locally produced beef and the flavor-derived type of beef traditionally consumed. Drivers of pork consumer liking have been shown to be affected by pH, color, water holding capacity, animal diet, and the presence of boar taint compounds. While tenderness and juiciness continue to be drivers of consumer liking for pork, flavor, as impacted by animal diet and the presence of boar taint compounds, continues to be a driver for consumer liking. For lamb, the flavor, as affected by diet, and animal age continue to be the main drivers of consumer liking. Lamb consumers vary across countries based on the level of consumption and preferences for flavor based on cultural effects and production practices.
The Influence of the Early Childhood Education and Care Environment on Young Children’s Physical Activity: Development and Reliability of the PLAYCE Study Environmental Audit and Educator Survey
Authors: Maitland Clover , Lester Leanne , Trost Stewart G. , Rosenberg Michael , Schipperijn Jasper , Trapp Georgina , Bai Pulan , Christian Hayley
Published: April 2020

(1) Background: Participation in physical activity is crucial for the healthy growth and development of young children. More robust measurement of environmental influences on children’s physical activity in early childhood education and care (ECEC) settings may help resolve inconsistencies in the literature. This study evaluated the reliability of an environmental audit and educator practice survey for assessing ECEC physical, policy, and social environments related to young children’s physical activity. (2) Methods: A convenience sample of 20 ECEC centres participated in this PLAYCE (Play Spaces and Environments for Children’s Physical Activity) sub-study. Trained auditors conducted audits and educators completed surveys, two weeks apart. Test-retest reliability of the survey (n = 32), inter-rater (n = 20 pairs) and intra-rater reliability (n = 38) of the audit was assessed using intra-class correlation coefficients (ICCs), Kappa statistics and percent agreement. (3) Results: Intra-rater and inter-rater reliability ICCs for outdoor equipment, spaces and features were good to excellent (ICC = 0.70–0.94), while ratings for indoor equipment, media and spaces varied from fair to excellent (ICC = 0.46–0.78). The majority of items were rated by Kappa as moderate or above for intra-rater, inter-rater and survey test-retest reliability. (4) Conclusions: The PLAYCE Study instruments provide reliable measures of ECEC physical activity environments which can help to better understand influences on young children’s physical activity.
Effects of Regular Taekwondo Intervention on Oxidative Stress Biomarkers and Myokines in Overweight and Obese Adolescents
Authors: Roh Hee-Tae , Cho Su-Youn , So Wi-Young
Published: April 2020

Purpose: Regular exercise can alleviate oxidative stress related to obesity and can induce secretion of myokines that are involved in the regulation of metabolic homeostasis. There are no studies examining changes in these variables as a result of Taekwondo training intervention. We aimed to investigate the effect of Taekwondo training on oxidative stress and myokine levels in overweight and obese adolescents. Methods: We randomly assigned 20 overweight and obese adolescents to control (control group; CG, n = 10) and experimental (experimental group; EG, n = 10) groups. The EG performed Taekwondo training five times a week for 16 weeks. Physical parameters (height, weight, body mass index (BMI)), physical fitness (maximal oxygen uptake (VO2max) (cardiorespiratory endurance), grip and leg strength (muscular strength), sit-and-reach (flexibility), Sargent jump (power), and stork stand test (balance)) were measured before and after intervention. We measured levels of serum oxidative stress markers (plasma malondialdehyde (MDA) and superoxide dismutase (SOD)) and myokines (serum interleukin-15 (IL-15), brain-derived neurotrophic factor (BDNF), irisin, and myostatin). Results: The weight and BMI in the EG after intervention were significantly lower and leg strength (muscular strength), sit-and-reach (flexibility), and Sargent jump (power) were significantly improved compared to those of the CG (p < 0.05). There were no significant interaction effects in terms of height, VO2 max, grip strength, or stork stand test (p > 0.05). The SOD and BDNF level after intervention were significantly higher in the EG after the intervention, whereas MDA and irisin levels were significantly lower than those of the CG (p < 0.05). There were no significant interaction effects in terms of serum IL-15 and myostatin levels (p > 0.05). Conclusions: Taekwondo training can reduce obesity and increase physical fitness with respect to muscular strength, flexibility, and power as well as alleviate oxidative stress and modulate myokine secretion in adolescents.
Association between Urinary Levels of Aflatoxin and Consumption of Food Linked to Maize or Cow Milk or Dairy Products
Authors: Ferri Fulvio , Brera Carlo , De Santis Barbara , Collini Giorgia , Crespi Enrica , Debegnach Francesca , Gargano Angelo , Gattei Daniela , Magnani Ines , Mancuso Pamela , Mozzanica Stefania , Teodori Elvira , Djuric Olivera , Giorgi Rossi Paolo
Published: April 2020

The aim of this analysis was to assess the association between consumption of maize and dairy products and urine and serum levels of aflatoxin FM1 (AFM1) in a sample of 59 males occupationally exposed (29) and non-exposed (30) to aflatoxins. Two urine samples were collected for each person; each sample was accompanied by a questionnaire on food consumption in the preceding 96 h. Given the similar levels of contamination found in exposed and non-exposed workers, the association between food consumption and AFM1 levels was analyzed by pooling samples from exposed and non-exposed workers. No serum sample was found to be positive for AFM1, whereas 74% of the urine samples were positive; the average concentration of positive samples was 0.042 ng/mL (range < limit of detection (LoD) (0.002)–0.399 ng/mL). Of the 21 samples from maize consumers, 13 were positive for AFM1 (62%), with a mean concentration of 0.026 ng/mL (range 0.006–0.088 ng/mL), while 76% (74/94) of the samples from maize non-consumers were positive (mean 0.045, range < LoD (0.002)–0.399 ng/mL). No association was found with milk or dairy products. The high urine level of aflatoxins found in both exposed and non-exposed workers was not associated with the consumption of maize or cow milk products.
Importance and Diagnosis of Flexibility Preparation of Male Sport Climbers
Authors: Draga Paweł , Ozimek Mariusz , Krawczyk Marcin , Rokowski Robert , Nowakowska Marcelina , Ochwat Paweł , Jurczak Adam , Stanula Arkadiusz
Published: April 2020

The objective of the study was to verify the relationships between sport skill levels and to identify the tests that accurately diagnose flexibility of sport climbers. This study examined 60 competitive advanced–higher elite male 7b–9a redpoint (RP) climbers. The athletes performed commonly used flexibility tests (stand-and-reach, straddle sit, straddle stand) and climbing-specific flexibility tests. Significant correlations were found between sport skill levels for the straddle stand test (r = −0.48) and the straddle sit test (r = −0.41). No significant correlations were observed between climbing-specific flexibility tests and sports skill level of climbers. Hip abduction evaluated using the straddle sit and straddle stand tests were significantly correlated with sports skill level and thus can be approached as a tool to diagnose flexibility of climbers. Flexibility is very specific and difficult to diagnose in climbing, but it should be developed.
Quantitative Proteomic Analysis of Alligator Weed Leaves Reveals That Cationic Peroxidase 1 Plays Vital Roles in the Potassium Deficiency Stress Response
Authors: Li Li-Qin , Lyu Cheng-Cheng , Li Jia-Hao , Wan Chuan-Yin , Liu Lun , Xie Min-Qiu , Zuo Rui-Jie , Ni Su , Liu Fan , Zeng Fu-Chun , Lu Yi-Fei , Yu Li-Ping , Huang Xue-Li , Wang Xi-Yao , Lu Li-Ming
Published: April 2020

Alligator weed is reported to have a strong ability to adapt to potassium deficiency (LK) stress. Leaves are the primary organs responsible for photosynthesis of plants. However, quantitative proteomic changes in alligator weed leaves in response to LK stress are largely unknown. In this study, we investigated the physiological and proteomic changes in leaves of alligator weed under LK stress. We found that chloroplast and mesophyll cell contents in palisade tissue increased, and that the total chlorophyll content, superoxide dismutase (SOD) activity and net photosynthetic rate (PN) increased after 15 day of LK treatment, but the soluble protein content decreased. Quantitative proteomic analysis suggested that a total of 119 proteins were differentially abundant proteins (DAPs). KEGG analysis suggested that most represented DAPs were associated with secondary metabolism, the stress response, photosynthesis, protein synthesis, and degradation pathway. The proteomic results were verified using parallel reaction monitoring mass spectrometry (PRM–MS) analysis and quantitative real-time PCR (qRT-PCR)assays. Additional research suggested that overexpression of cationic peroxidase 1 of alligator weed (ApCPX1) in tobacco increased LK tolerance. The seed germination rate, peroxidase (POD) activity, and K+ content increased, and the hydrogen peroxide (H2O2) content decreased in the three transgenic tobacco lines after LK stress. The number of root hairs of the transgenic line was significantly higher than that of WT, and net K efflux rates were severely decreased in the transgenic line under LK stress. These results confirmed that ApCPX1 played positive roles in low-K+ signal sensing. These results provide valuable information on the adaptive mechanisms in leaves of alligator weed under LK stress and will help identify vital functional genes to apply to the molecular breeding of LK-tolerant plants in the future.
Role of Deubiquitinases in Human Cancers: Potential Targeted Therapy
Authors: Lai Keng Po , Chen Jian , Tse William Ka Fai
Published: April 2020

Deubiquitinases (DUBs) are involved in various cellular functions. They deconjugate ubiquitin (UBQ) from ubiquitylated substrates to regulate their activity and stability. Studies on the roles of deubiquitylation have been conducted in various cancers to identify the carcinogenic roles of DUBs. In this review, we evaluate the biological roles of DUBs in cancer, including proliferation, cell cycle control, apoptosis, the DNA damage response, tumor suppression, oncogenesis, and metastasis. This review mainly focuses on the regulation of different downstream effectors and pathways via biochemical regulation and posttranslational modifications. We summarize the relationship between DUBs and human cancers and discuss the potential of DUBs as therapeutic targets for cancer treatment. This review also provides basic knowledge of DUBs in the development of cancers and highlights the importance of DUBs in cancer biology.
A Tribute to Lewis Wolpert and His Ideas on the 50th Anniversary of the Publication of His Paper ‘Positional Information and the Spatial Pattern of Differentiation’. Evidence for a Timing Mechanism for Setting Up the Vertebrate Anterior-Posterior (A-P) Axis
Authors: Durston Antony J.
Published: April 2020

This article is a tribute to Lewis Wolpert and his ideas on the occasion of the recent 50th anniversary of the publication of his article ‘Positional Information and the Spatial Pattern of Differentiation’. This tribute relates to another one of his ideas: his early ‘Progress Zone’ timing model for limb development. Recent evidence is reviewed showing a mechanism sharing features with this model patterning the main body axis in early vertebrate development. This tribute celebrates the golden era of Developmental Biology.
The Effect of Temperature on the Development of Spodoptera frugiperda (Lepidoptera: Noctuidae)
Authors: Du Plessis Hannalene , Schlemmer Marie-Louise , Van den Berg Johnnie
Published: April 2020

The fall armyworm (Spodoptera frugiperda) is a pest of tropical origin which recently invaded Africa, the Far East and Australia. Temperature, therefore, plays an important role in its invasion biology, since this pest does not go into diapause. The aim of this study was to determine the development rate of S. frugiperda at different temperatures and to calculate the number of degree-days (°D) required for each stage to complete its development. This study was conducted at five different temperatures—18, 22, 26, 30 and 32 ± 1 °C. Larvae were reared individually in Petri dishes with sweetcorn kernels provided as food. The development rate of S. frugiperda increased linearly with increasing temperatures between 18 and 30 °C and larval survival was the highest between 26 and 30 °C. The optimal range for egg, larval and egg-to-adult development was between 26 and 30 °C. The optimum temperature with the fastest larval development rate and lowest mortality was at 30 °C. The pupal development period ranged between 7.82 and 30.68 days (32–18 °C). The minimum temperature threshold for egg and larva development was 13.01 and 12.12 °C, respectively, 13.06 °C for pupae and 12.57 °C for egg-to-adult development. Degree-day requirements for the development of the respective life cycle stages of S. frugiperda were 35.68 ± 0.22 for eggs, 204.60 ± 1.23 °D for larvae, 150.54 ± 0.93 °D for pupae and 391.61 ± 1.42 °D for egg-to-adult development.
Thyroid Hormone Diseases and Osteoporosis
Authors: Delitala Alessandro P. , Scuteri Angelo , Doria Carlo
Published: April 2020

Thyroid hormones are essential for normal skeletal development and normal bone metabolism in adults but can have detrimental effects on bone structures in states of thyroid dysfunction. Untreated severe hyperthyroidism influences the degree of bone mass and increases the probability of high bone turnover osteoporosis. Subclinical hyperthyroidism, defined as low thyrotropin (TSH) and free hormones within the reference range, is a subtler disease, often asymptomatic, and the diagnosis is incidentally made during screening exams. However, more recent data suggest that this clinical condition may affect bone metabolism resulting in decreased bone mineral density (BMD) and increased risk of fracture, particularly in postmenopausal women. The main causes of exogenous subclinical hyperthyroidism are inappropriate replacement dose of thyroxin and TSH suppressive L-thyroxine doses in the therapy of benign thyroid nodules and thyroid carcinoma. Available data similarly suggest that a long-term TSH suppressive dose of thyroxin may decrease BMD and may induce an increased risk of fracture. These effects are particularly observed in postmenopausal women but are less evident in premenopausal women. Overt hypothyroidism is known to lower bone turnover by reducing both osteoclastic bone resorption and osteoblastic activity. These changes in bone metabolism would result in an increase in bone mineralization. At the moment, there are no clear data that demonstrate any relationship between BMD in adults and hypothyroidism. Despite these clinical evidences, the cellular and molecular actions of thyroid hormones on bone structures are not complete clear.
On the Vibrations and Stability of Moving Viscoelastic Axially Functionally Graded Nanobeams
Authors: Shariati Ali , Jung Dong won , Mohammad-Sedighi Hamid , Żur Krzysztof Kamil , Habibi Mostafa , Safa Maryam
Published: April 2020

In this article, size-dependent vibrations and the stability of moving viscoelastic axially functionally graded (AFG) nanobeams were investigated numerically and analytically, aiming at the stability enhancement of translating nanosystems. Additionally, a parametric investigation is presented to elucidate the influence of various key factors such as axial gradation of the material, viscosity coefficient, and nonlocal parameter on the stability boundaries of the system. Material characteristics of the system vary smoothly along the axial direction based on a power-law distribution function. Laplace transformation in conjunction with the Galerkin discretization scheme was implemented to obtain the natural frequencies, dynamical configuration, divergence, and flutter instability thresholds of the system. Furthermore, the critical velocity of the system was evaluated analytically. Stability maps of the system were examined, and it can be concluded that the nonlocal effect in the system can be significantly dampened by fine-tuning of axial material distribution. It was demonstrated that AFG materials can profoundly enhance the stability and dynamical response of axially moving nanosystems in comparison to homogeneous materials. The results indicate that for low and high values of the nonlocal parameter, the power index plays an opposite role in the dynamical behavior of the system. Meanwhile, it was shown that the qualitative stability of axially moving nanobeams depends on the effect of viscoelastic properties in the system, while axial grading of material has a significant role in determining the critical velocity and natural frequencies of the system.
A Novel Approach to Improve the Microstructure and Mechanical Properties of Al–Mg–Si Aluminum Alloys during Twin-Roll Casting
Authors: Li Yong , He Chen , Li Jiadong , Wang Zhaodong , Wu Di , Xu Guangming
Published: April 2020

The main purpose of this present study was to investigate the different processing conditions on the microstructure, segregation behavior of alloying elements, and mechanical properties of Al−Mg−Si alloy twin-roll cast slab prepared using a novel twin-roll casting technology. The simulation of temperature field, distribution of alloying elements, tensile properties, hardness, and conductivity were examined by a Leica optical microscope, scanning electron microscopy, energy dispersion spectroscopy, electron probe microanalysis, and tensile tests. The results indicated that when the traditional twin-roll casting method was used to produce aluminum alloy strip, there are obvious centerline segregation defects due to the deep crystallization front depth and symmetrical solidification characteristics. When the forced-cooling technology was applied in the twin-roll casting process, by virtue of the changing of crystallization front depth and crystallization front shape, the segregation defects are obviously suppressed. Suggesting that this method can significantly improve the uniformity of alloying elements in the thickness direction of the twin-roll cast slab, ultimately improve the mechanical properties of AA6022 aluminum alloy.
Study on the Properties and Process Parameters of Different Clays in Disc Granulation
Authors: Li Hui , Zhang Jingjie , Zheng Wukui , Cui Tian , Yang Yuxuan
Published: April 2020

Sintering solidification is an effective way to treat soil contaminated with nonvolatile heavy metal. The ceramsite prepared from contaminated soil after sintering can be used as lightweight aggregate in concrete. The preparation process of ceramsite can be divided into two steps: granulation and sintering. As one of the key processes, granulation is directly related to the final solidification and physical properties of ceramsite, and the properties of the clay are directly related to the granulation process. In this work, clays from different regions granulated with disc granulation were studied and compared. The results showed that different clays had significantly different performances in granulation with the same granulation system, and each clay had its own best process parameter. The significance analysis showed that the volume surface mean diameter and the reduction ratio had the most significant impact on the granulated fraction among all the factors. No matter which process parameter was used, as the particle size increased, the granulated fraction increased first and then decreased, and the best results were obtained when the average volume diameter was about 20.5 µm. Furthermore, as the reduction ratio increased, the granulated fraction decreased. These two factors are easy to measure and can be used for predicting the granulation effect of different clays, which can further guide industrial production.
Platinum Group Elements Recovery from Used Catalytic Converters by Acidic Fusion and Leaching
Authors: Prasetyo Erik , Anderson Corby
Published: April 2020

The recovery of platinum group elements (PGE (platinum group element coating); Pd, Pt, and Rh) from used catalytic converters, using low energy and fewer chemicals, was developed using potassium bisulfate fusion pretreatment, and subsequently leached using hydrochloric acid. In the fusion pre-treatment, potassium bisulfate alone (without the addition of an oxidant) proved to be an effective and selective fusing agent. It altered PGE into a more soluble species and did not react with the cordierite support, based on X-Ray Diffraction (XRD) and metallographic characterization results. The fusion efficacy was due to the transformation of bisulfate into pyrosulfate, which is capable of oxidizing PGE. However, the introduction of potassium through the fusing agent proved to be detrimental, in general, since potassium formed insoluble potassium PGE chloro-complexes during leaching (decreasing the recovery) and required higher HCl concentration and a higher leaching temperature to restore the solubility. Optimization on the fusion and leaching parameter resulted in 106% ± 1.7%, 93.3% ± 0.6%, and 94.3% ± 3.9% recovery for Pd, Pt, and Rh, respectively. These results were achieved at fusion conditions: temperature 550 °C, potassium bisulfate/raw material mass ratio 2.5, and fusion time within 30 min. The leaching conditions were: HCl concentration 5 M, temperature 80 °C, and time within 20 min.
Microfabrication of Ni-Fe Mold Insert via Hard X-ray Lithography and Electroforming Process
Authors: Park Jae Man , Park Sung Cheol , Shin Da Seul , Kim Jong Hyun , Cho Hanlyun , Yang Woo Seok , Son Seong Ho , Park Seong Jin
Published: April 2020

In this research, a Ni-Fe mold insert for the efficient replication of high aspect-ratio microstructure arrays was fabricated via hard X-ray lithography and an electroforming process. For the X-ray exposure on a photoresist, a gold-based X-ray mask was prepared with conventional UV photolithography. The gold thickness was designed to be over 15 μm to prevent development underneath the absorber and to enhance the adhesion strength between the photoresist and substrate. By using the X-ray mask, a positive-type photoresist was selectively exposed to X-ray under an exposure energy of 4 kJ/cm3. Thereafter, the exposed region was developed in a downward direction to effectively remove the residual photoresist from the substrate. During the evaporation process, deionized water mixed with a surface additive prevented the bending and clustering of the photoresist microstructure arrays by lowering the capillary force, resulting in a defect-free mother structure for electroforming. Lastly, the mother structure was uniformly Ni-Fe electroformed on a conductive substrate without the formation of any pores or detachment from the substrate. Based on the proposed microfabrication process, a Ni-Fe mold insert with a 183 μm pattern size, 68 μm gap size, 550 μm height, 2116 microcavities and a hardness of 585 Hv was precisely manufactured. It can be utilized for the mass production of high aspect ratio metal and ceramic microstructure arrays in micro molding technologies.
Effect of TiO2 and ZnO Nanoparticles on the Performance of Dielectric Nanofluids Based on Vegetable Esters During Their Aging
Authors: Fernández Inmaculada , Valiente Rafael , Ortiz Félix , Renedo Carlos J. , Ortiz Alfredo
Published: April 2020

Over the last few decades the insulating performance of transformer oils has been broadly studied under the point of view of nanotechnology, which tries to improve the insulating and heat dissipation performance of transformer oils by suspending nanoparticles. Many authors have analyzed the thermal and dielectric behavior of vegetable oil based-nanofluids, however, very few works have studied the evolution of these liquids during thermal aging and their stability. In this paper has been evaluated the performance of aged vegetable oil based-nanofluids, which have been subjected to accelerated thermal aging at 150 °C. Nanoparticles of TiO2 and ZnO have been dispersed in a commercial natural ester. Breakdown voltage, resistivity, dissipation factor and acidity of nanofluid samples have been measured according to standard methods, as well as stability. Moreover, it has been analyzed the degradation of Kraft paper through the degree of polymerization (DP). The results have showed that although nanoparticles improve breakdown voltage, they increase the ageing of insulation liquids and dielectric paper.
A Multi-Decadal Investigation of Tidal Creek Wetland Changes, Water Level Rise, and Ghost Forests
Authors: Magolan Jessica Lynn , Halls Joanne Nancie
Published: April 2020

Coastal wetlands play a vital role in protecting coastlines, which makes the loss of forested and emergent wetlands devastating for vulnerable coastal communities. Tidal creeks are relatively small hydrologic areas that feed into larger estuaries, are on the front lines of the interface between saltwater and freshwater ecosystems, and are potentially the first areas to experience changes in sea level. The goal of this study was to investigate wetland changes through time at two tidal creeks (Smith Creek and Town Creek) of the Cape Fear River estuary in southeastern North Carolina, USA, to determine if there is a spatial relationship between habitat change, physical geography characteristics, and the rate of wetland migration upstream. Historic aerial photography and recent satellite imagery were used to map land cover and compute change through time and were compared with derived physical geography metrics (sinuosity, creek width, floodplain width, floodplain elevation, and creek slope). The primary results were: (1) there was a net gain in emergent wetlands even accounting for the area of wetlands that became water, (2) wetlands have migrated upstream at an increasing rate through time, (3) land cover change was significantly different between the two creeks (P = 0.01) where 14% (67.5 ha) of Smith Creek and 18% (272.3 ha) of Town Creek transitioned from forest to emergent wetland, and (4) the transition from emergent wetland to water was significantly related to average change in creek width, floodplain elevation, and average water level. In conclusion, this research correlated habitat change with rising water level and identified similarities and differences between neighboring tidal creeks. Future research could apply the methodologies developed here to other coastal locations to further explore the relationships between tides, sea level, land cover change, and physical geography characteristics.
Impacts of Assimilating ATMS Radiances on Heavy Rainfall Forecast in RMAPS-ST
Authors: Xie Yanhui , Chen Min , Shi Jiancheng , Fan Shuiyong , He Jing , Dou Youjun
Published: April 2020

The Advanced Technology Microwave Sounder (ATMS) mounted on the Suomi National Polar-Orbiting Partnership (NPP) satellite can provide both temperature and humidity information for a weather prediction model. Based on the rapid-refresh multi-scale analysis and prediction system—short-term (RMAPS-ST), we investigated the impact of ATMS radiance data assimilation on strong rainfall forecasts. Two groups of experiments were conducted to forecast heavy precipitation over North China between 18 July and 20 July 2016. The initial conditions and forecast results from the two groups of experiments have been compared and evaluated against observations. In comparison with the first group of experiments that only assimilated conventional observations, some added value can be obtained for the initial conditions of temperature, humidity, and wind fields after assimilating ATMS radiance observations in the system. For the forecast results with the assimilation of ATMS radiances, the score skills of quantitative forecast rainfall have been improved when verified against the observed rainfall. The Heidke skill score (HSS) skills of 6-h accumulated precipitation in the 24-h forecasts were overall increased, more prominently so for the heavy rainfall above 25 mm in the 0–6 h of forecasts. Assimilating ATMS radiance data reduced the false alarm ratio of quantitative precipitation forecasting in the 0–12 h of the forecast range and thus improved the threat scores for the heavy rainfall storm. Furthermore, the assimilation of ATMS radiances improved the spatial distribution of hourly rainfall forecast with observations compared with that of the first group of experiments, and the mean absolute error was reduced in the 10-h lead time of forecasts. The inclusion of ATMS radiances provided more information for the vertical structure of features in the temperature and moisture profiles, which had an indirect positive impact on the forecasts of the heavy rainfall in the RMAPS-ST system. However, the deviation in the location of the heavy rainfall center requires future work.
Validating GEV Model for Reflection Symmetry-Based Ocean Ship Detection with Gaofen-3 Dual-Polarimetric Data
Authors: Guo Rui , Cui Jingyu , Jing Guobin , Zhang Shuangxi , Xing Mengdao
Published: April 2020

The spaceborne synthetic aperture radar (SAR) is quite powerful in worldwide ocean observation, especially for ship monitoring, as a hot topic in ocean surveillance. The launched Gaofen-3 (GF3) satellite of China can provide C-band and multi-polarization SAR data, and one of its scientific applications is ocean ship detection. Compared with the single polarization system, polarimetric systems can be used for more effective ship detection. In this paper, a generalized extreme value (GEV)-based constant false alarm rate (CFAR) detector is proposed for ship detection in the ocean by using the reflection symmetry metric of dual-polarization. The reflection symmetry property shows big differences between the metallic targets at sea and the sea surface. In addition, the GEV statistical model is employed for reflection symmetry statistical distribution, which fits the reflection symmetry probability density function (pdf) well. Five dual-polarimetric GF3 stripmap ocean data sets are introduced in the paper, to show the contrast in enhancement by using reflection symmetry and to investigate the GEV model fit to the reflection symmetry metric. Additionally, with the detection experiments on the real GF3 datasets, the effectiveness and efficiency of the GEV model for reflection symmetry and the model-based ocean ship detector are verified.