bluuebunny/crossref_metadata_2025 huggingface dataset:
Automated Scheduling Approach under Smart Contract for Remote Wind Farms with Power-to-Gas Systems in Multiple Energy Markets
Authors: Ji Zhenya , Guo Zishan , Li Hao , Wang Qi
Published: October 2021

The promising power-to-gas (P2G) technology makes it possible for wind farms to absorb carbon and trade in multiple energy markets. Considering the remoteness of wind farms equipped with P2G systems and the isolation of different energy markets, the scheduling process may suffer from inefficient coordination and unstable information. An automated scheduling approach is thus proposed. Firstly, an automated scheduling framework enabled by smart contract is established for reliable coordination between wind farms and multiple energy markets. Considering the limited logic complexity and insufficient calculation of smart contracts, an off-chain procedure as a workaround is proposed to avoid complex on-chain solutions. Next, a non-linear model of the P2G system is developed to enhance the accuracy of scheduling results. The scheduling strategy takes into account not only the revenues from multiple energy trades, but also the penalties for violating contract items in smart contracts. Then, the implementation of smart contracts under a blockchain environment is presented with multiple participants, including voting in an agreed scheduling result as the plan. Finally, the case study is conducted in a typical two-stage scheduling process—i.e., day-ahead and real-time scheduling—and the results verify the efficiency of the proposed approach.
A Comparative Analysis of the ARIMA and LSTM Predictive Models and Their Effectiveness for Predicting Wind Speed
Authors: Elsaraiti Meftah , Merabet Adel
Published: October 2021

Forecasting wind speed has become one of the most attractive topics to researchers in the field of renewable energy due to its use in generating clean energy, and the capacity for integrating it into the electric grid. There are several methods and models for time series forecasting at the present time. Advancements in deep learning methods characterize the possibility of establishing a more developed multistep prediction model than shallow neural networks (SNNs). However, the accuracy and adequacy of long-term wind speed prediction is not yet well resolved. This study aims to find the most effective predictive model for time series, with less errors and higher accuracy in the predictions, using artificial neural networks (ANNs), recurrent neural networks (RNNs), and long short-term memory (LSTM), which is a special type of RNN model, compared to the common autoregressive integrated moving average (ARIMA). The results are measured by the root mean square error (RMSE) method. The comparison result shows that the LSTM method is more accurate than ARIMA.
Power Electronics Programmable Voltage Source with Reduced Ripple Component of Output Signal Based on Continuous-Time Sigma-Delta Modulator
Authors: Gwóźdź Michał
Published: October 2021

In this work, an idea of a wideband, precision, power electronics programmable voltage source (PVS) is presented. One of the basic elements of the converter, the control section, contains a continuous-time sigma-delta modulator (SDM) with a pair of interconnected complementary comparators, which represents a new approach. In this case, the SDM uses comparators with a dynamic hysteresis loop (DHC) that includes an AC circuit rather than an R-R network. Dynamic hysteresis is a very effective way of eliminating parasitic oscillation during the signal transition at the input of the comparator; it also affects the frequency characteristics and, especially, the phase properties of the comparator, and this phenomenon is exploited in the proposed converter. The main disadvantage of all pulse-modulated converters is the presence of a ripple component in the output voltage (current), which reduces the quality of the output signal and may cause high-frequency disturbances. A basic feature of PVS is a lower RMS value for the pulse modulation component in the output voltage of the converter, compared to the typical value. Another important feature of the proposed converter is the ability of precise mapping of the output voltage to the reference (input) signal. The structure of the control circuit is relatively simple—no complex, digital components are used. Due to the high frequency of the SDM output bit-stream, the simulation model of the power stage of PVS is based on the power modules with gallium-nitride field effect transistors (GaN FETs). The work discusses the rules of PVS operations and the results from PVS simulation model studies as well as highlights the possible application fields for systems with a PVS.
The Viability of Providing 24-Hour Electricity Access to Off-Grid Island Communities in the Philippines
Authors: Lozano Lorafe , Querikiol Edward M. , Taboada Evelyn B.
Published: October 2021

Techno-economic viability assessments of rural electrification projects, especially those that integrate renewable energy technologies, typically look at system design optimization that would yield the most favorable cost and investment scenarios. However, the true viability of these projects relies more importantly on their impact to the rural communities while ensuring positive financial returns to the project developers. This paper aims to expand the viability assessment of electrification projects in off-grid island communities in order to mainly address the apparently opposing needs of the major stakeholders at play by developing a viability assessment framework considering the techno-economic dimensions as well as the socio-economic impacts to the consumers. The analysis follows a two-phase approach, where system design optimization and financial impact calculations are done in the first phase and the socio-economic viability is accomplished in the second phase. Results suggest that high capital investment for renewable energy has a better pay-off when there is higher demand for electricity. On the other hand, consumers also tend to receive higher economic benefit as they consume more electricity. However, the low income of rural consumers strains their capacity to pay, which necessitates their engagement in more economically-productive uses of electricity. The viability assessment framework can be a useful tool for both investors and consumers as this provides important insights which can be translated into impactful interventions that may include government support through improved policy implementation that can positively sustain electricity access in off-grid communities through renewable energy.
Reduction of Total Harmonic Distortion of Wind Turbine Active Power Using Blade Angle Adaptive PI Controller
Authors: Shawqran Ahmed M. , El-Marhomy Abdallah , Sameh Mariam A. , Attia Mahmoud A.
Published: October 2021

Power quality can have a large detrimental effect on industrial processes and the commercial sector. Thus, this paper proposes a new technique to improve the power quality of electric power systems. This technique relies on auto-adjusting of the blade angle to mitigate the harmonics in wind generator active power. A new adaptive PI blade-angle controller is applied in this technique to reduce the total harmonic distortion (THD) of the output power. The parameters of the adaptive PI controller are initialized by using the Harmony Search algorithm (HSA), hybrid Harmony Search optimization and Equilibrium optimization (EO), and hybrid Harmony Search optimization and Teaching learning-based optimization (TLBO). The execution of the optimization algorithms relies mainly on the optimization objective function. Two optimization objective functions are mathematically modeled and compared to enhance the power quality. The first one is to minimize the sum square of error, while the second objective is to minimize the THD. Many case studies are applied with various wind-speed profiles under normal and faulty conditions. Results show the superiority of HSA hybrid EO algorithm with the second objective functions through reducing the harmonics and enhancing the power quality. Moreover, laboratory studies are applied to investigate the effect of the blade-angle variations on the extracted active power.
Insurance Programs in the Renewable Energy Sources Projects
Authors: Kirillova Nadezda , Pukala Ryszard , Janowicz-Lomott Marietta
Published: October 2021

The development of projects using renewable energy sources (RES) necessitates the development of insurance programs and systems. This involves identifying and assessing the risks of renewable energy projects in the transition to new types of energy, determining typical corporate and specific risks, the need and content of the main types, forms of insurance contracts, assessing the financial condition, and choosing insurance organizations and reinsurance programs. This article focuses on the formation of such insurance programs, their interaction with industrial safety systems and ensuring corporate participation in achieving sustainable development goals; as well as selection and assessment of the insurer financial stability and the insurance RES programs economic efficiency.
Bioconversion of Crude Glycerol into 1,3-Propanediol(1,3-PDO) with Bioelectrochemical System and Zero-Valent Iron Using Klebsiella pneumoniae L17
Authors: Kong Da Seul , Park Eun Joo , Mutyala Sakuntala , Kim Minsoo , Cho Yunchul , Oh Sang Eun , Kim Changman , Kim Jung Rae
Published: October 2021

Crude glycerol is a major byproduct in the production of biodiesel and contains a large number of impurities. The transformation of crude glycerol into valuable compounds such as 1,3-propanediol (1,3-PDO) using clean and renewable processes, like bioconversion, is an important task for the future of the chemical industry. In this study, 1,3-PDO bioproductions from crude and pure glycerol were estimated as 15.4 ± 0.8 and 11.4 ± 0.1 mmol/L, respectively. Because 1,3-PDO is a reductive metabolite that requires additional reducing energy, external supplements of electron for further improvement of 1,3-PDO biosynthesis were attempted using a bioelectrochemical system (BES) or zero-valent iron (ZVI). The conversions of crude and pure glycerol under electrode and iron-based cultivation were investigated for 1,3-PDO production accompanied by metabolic shift and cell growth. The BES-based conversion produced 32.6 ± 0.6 mmol/L of 1,3-PDO with ZVI implementation.
Novel Instantaneous Wavelet Bicoherence for Vibration Fault Detection in Gear Systems
Authors: Gelman Len , Soliński Krzysztof , Ball Andrew
Published: October 2021

Higher order spectra exhibit a powerful detection capability of low-energy fault-related signal components, buried in background random noise. This paper investigates the powerful nonlinear non-stationary instantaneous wavelet bicoherence for local gear fault detection. The new methodology of selecting frequency bands that are relevant for wavelet bicoherence fault detection is proposed and investigated. The capabilities of wavelet bicoherence are proven for early-stage fault detection in a gear pinion, in which natural pitting has developed in multiple pinion teeth in the course of endurance gearbox tests. The results of the WB-based fault detection are compared with a stereo optical fault evaluation. The reliability of WB-based fault detection is quantified based on the complete probability of correct identification. This paper is the first attempt to investigate instantaneous wavelet bicoherence technology for the detection of multiple natural early-stage local gear faults, based on comprehensive statistical evaluation of the industrially relevant detection effectiveness estimate—the complete probability of correct fault detection.
Improving Machine-Learning Diagnostics with Model-Based Data Augmentation Showcased for a Transformer Fault
Authors: Kahlen Jannis N. , Andres Michael , Moser Albert
Published: October 2021

Machine-learning diagnostic systems are widely used to detect abnormal conditions in electrical equipment. Training robust and accurate diagnostic systems is challenging because only small databases of abnormal-condition data are available. However, the performance of the diagnostic systems depends on the quantity and quality of the data. The training database can be augmented utilizing data augmentation techniques that generate synthetic data to improve diagnostic performance. However, existing data augmentation techniques are generic methods that do not include additional information in the synthetic data. In this paper, we develop a model-based data augmentation technique integrating computer-implementable electromechanical models. Synthetic normal- and abnormal-condition data are generated with an electromechanical model and a stochastic parameter value sampling method. The model-based data augmentation is showcased to detect an abnormal condition of a distribution transformer. First, the synthetic data are compared with the measurements to verify the synthetic data. Then, ML-based diagnostic systems are created using model-based data augmentation and are compared with state-of-the-art diagnostic systems. It is shown that using the model-based data augmentation results in an improved accuracy compared to state-of-the-art diagnostic systems. This holds especially true when only a small abnormal-condition database is available.
Mechanism of Solute and Thermal Characteristics in a Casson Hybrid Nanofluid Based with Ethylene Glycol Influenced by Soret and Dufour Effects
Authors: Hafeez Muhammad Bilal , Sumelka Wojciech , Nazir Umar , Ahmad Hijaz , Askar Sameh
Published: October 2021

This article models a system of partial differential equations (PDEs) for the thermal and solute characteristics under gradients (concentration and temperature) in the magnetohydrodynamic flow of Casson liquid in a Darcy porous medium. The modelled problems are highly non-linear with convective boundary conditions. These problems are solved numerically with a finite element approach under a tolerance of 10−8. A numerical algorithm (finite element approach) is provided and a numerical procedure is discussed. Convergence is also observed via 300 elements. Simulations are run to explore the dynamics of flow and the transport of heat and mass under parametric variation. To examine the impact of a temperature gradient on the transport of mass and the role of a concentration gradient on the transport of heat energy, simulations are recorded. Remarkable changes in temperature and concentration are noted when Dufour and Soret numbers are varied.
Kinetic and Thermodynamic Analysis of High-Pressure CO2 Capture Using Ethylenediamine: Experimental Study and Modeling
Authors: Villarroel Josselyne A. , Palma-Cando Alex , Viloria Alfredo , Ricaurte Marvin
Published: October 2021

One of the alternatives to reduce CO2 emissions from industrial sources (mainly the oil and gas industry) is CO2 capture. Absorption with chemical solvents (alkanolamines in aqueous solutions) is the most widely used conventional technology for CO2 capture. Despite the competitive advantages of chemical solvents, the technological challenge in improving the absorption process is to apply alternative solvents, reducing energy demand and increasing the CO2 captured per unit of solvent mass. This work presents an experimental study related to the kinetic and thermodynamic analysis of high-pressure CO2 capture using ethylenediamine (EDA) as a chemical solvent. EDA has two amine groups that can increase the CO2 capture capacity per unit of solvent. A non-stirred experimental setup was installed and commissioned for CO2 capture testing. Tests of the solubility of CO2 in water were carried out to validate the experimental setup. CO2 capture testing was accomplished using EDA in aqueous solutions (0, 5, 10, and 20 wt.% in amine). Finally, a kinetic model involving two steps was proposed, including a rapid absorption step and a slow diffusion step. EDA accelerated the CO2 capture performance. Sudden temperature increases were observed during the initial minutes. The CO2 capture was triggered after the absorption of a minimal amount of CO2 (~10 mmol) into the liquid solutions, and could correspond to the “lean amine acid gas loading” in a typical sweetening process using alkanolamines. At equilibrium, there was a linear relationship between the CO2 loading and the EDA concentration. The CO2 capture behavior obtained adapts accurately (AAD < 1%) to the kinetic mechanism.
A Bibliometric Review on Decision Approaches for Clean Energy Systems under Uncertainty
Authors: Pandey Alok K. , Krishankumar R. , Pamucar Dragan , Cavallaro Fausto , Mardani Abbas , Kar Samarjit , Ravichandran K. S.
Published: October 2021

This paper aims to provide a bibliometric review on the diverse decision approaches in uncertain contexts for clean energy system (CES) assessment. A total of 126 publications are analyzed. Previous reviews on CES have discussed several research questions on the decision methods and the applicability of evaluating CES, along with the factors associated with CESs. In the present study, we focus on the bibliometric aspect that attempts to address questions related to the prominence of authors, countries/regions that focus on the current theme, impact of journals, importance of articles in the research community, and so on. The window considered for the study is from 2018 to 2021, with the motive to extend the review process from the preceding works. A review model is presented to address the questions based on the literature evidence. The results infer that CESs are the most viable mode for sustainable development, and the use of decision approaches is apt for the assessment of CESs.
Prospects of Integrated Photovoltaic-Fuel Cell Systems in a Hydrogen Economy: A Comprehensive Review
Authors: Ogbonnaya Chukwuma , Abeykoon Chamil , Nasser Adel , Turan Ali , Ume Cyril Sunday
Published: October 2021

Integrated photovoltaic-fuel cell (IPVFC) systems, amongst other integrated energy generation methodologies are renewable and clean energy technologies that have received diverse research and development attentions over the last few decades due to their potential applications in a hydrogen economy. This article systematically updates the state-of-the-art of IPVFC systems and provides critical insights into the research and development gaps needed to be filled/addressed to advance these systems towards full commercialization. Design methodologies, renewable energy-based microgrid and off-grid applications, energy management strategies, optimizations and the prospects as self-sustaining power sources were covered. IPVFC systems could play an important role in the upcoming hydrogen economy since they depend on solar hydrogen which has almost zero emissions during operation. Highlighted herein are the advances as well as the technical challenges to be surmounted to realize numerous potential applications of IPVFC systems in unmanned aerial vehicles, hybrid electric vehicles, agricultural applications, telecommunications, desalination, synthesis of ammonia, boats, buildings, and distributed microgrid applications.
Control of WPT Transmitter Coils for Power Distribution to Two Receiver Coils without Feedback
Authors: Heo Jun , Park Sungyeal , Kim Sang-Won , Cho In-Kui , Hong Songnam , Park Yong Bae
Published: October 2021

This paper proposes the algorithm to control the current ratio of the transmitting (Tx) coils for proper power distribution to the two receiving (Rx) coils in wireless power transfer (WPT) system. The proposed algorithm assumes that each Rx coil appears at different times to consider the situation where multiple users request power transmission as practically as possible. That is, suppose the second Rx coil enters the charging space later than the first Rx coil. When each coil enters the charging space, only the Tx coil is used to obtain the value required for calculation. Using the obtained result, the optimized Tx coil current is calculated by the proposed algorithm and proper power distribution to both Rx coils is achieved. Three Tx coils and two Rx coils are constructed using the ANSYS MAXWELL simulation tool. As a result of applying the proposed algorithm, it was confirmed that a similar level of power was transmitted between 40∼60%, respectively. The sum of the power transmitted to the two Rx coils also appeared as more than 75%.
Aging Characteristics of Contact Electrodes of Low Voltage DC Switches
Authors: Kim Hyosung
Published: October 2021

With the present state of the direct current (DC) distribution market, securing the safety of the DC distribution system is emerging as a major issue. Like AC distribution systems, DC switches and circuit breakers are one of the main means to ensure safety. However, in the DC system, since there is no current zero point in the load current, the phenomenon occurring when the circuit is cut off is different from that of the AC system, so technical research is required to cope with this. In this study, the aging characteristics of the contact electrode of a 400 V class low voltage DC (LVDC) switch is studied for the development of wall-mount switches or circuit breakers for residential houses. As an arc extinguishing method to break DC load current, a prototype experimental circuit breaker that uses a magnetic extinguishing method that is effective for blocking low voltage low power DC is invented, and an automated experiment system is established. The DC switch test repeats the operation of turning it on and off 13,000 times, and continuously evaluates the performance of the electric contacts by calculating the voltage drop between the electrode contacts and the corresponding Ohmic resistance value when conducting every 500 times. This paper tests six contact materials to compare the aging characteristics of them by evaluating contact resistance during the test period. AW18-Cu composite material showed the most stable and excellent contact performance for LVDC switches during the entire test operation period.
Accuracy of Simplified Modelling Assumptions on External and Internal Driving Forces in the Building Energy Performance Simulation
Authors: De Luca Giovanna , Bianco Mauthe Degerfeld Franz , Ballarini Ilaria , Corrado Vincenzo
Published: October 2021

The recently issued EN ISO 52016-1 technical standard provides a new simplified dynamic method for the building energy performance assessment. Since an extensive validation of the EN ISO 52016-1 hourly method is still missing, the present work investigates the effect of the main modelling assumptions—related to the heat balance on the outdoor and the indoor envelope surfaces—on the building thermal behaviour. The model validation was carried out by assessing the accuracy variation consequent to the application of the EN ISO 52016-1 modelling assumptions to a detailed dynamic calculation tool (EnergyPlus). To guarantee a general validity of the outcomes, two buildings, two levels of thermal insulation, and two Italian climatic zones were considered, for a total of eight case studies. To explore different applications of the standard method, the analysis was performed both under a free-floating condition—to evaluate the accuracy of the model in predicting the indoor operative temperatures—and to assess the annual energy needs for space heating and cooling. Results show that the assumptions related to the definition of the external convective and the shortwave (solar) radiation heat transfer lead to non-negligible inaccuracies in the EN ISO 52016-1 hourly model.
Tackling Dissipative Components Based on the SPECO Approach: A Cryogenic Heat Exchanger Used in Natural Gas Liquefaction
Authors: Cavalcanti Eduardo J. C. , Carvalho Monica
Published: October 2021

The cryogenic industry has been experiencing continuous progress in recent years, primarily due to the global development of oil and gas activities. Natural gas liquefaction is a cryogenic process, with the refrigeration system being crucial to the overall process. The objective of the study presented herein is to carry out an exergoeconomic assessment for a dual nitrogen expander process used to liquefy natural gas, employing the SPecific Exergy COsting (SPECO) methodology. The air coolers and throttling valve are dissipative components, which present fictitious unit cost rates that are reallocated to the final product (Liquefied Natural Gas). The liquefaction process has an exergy efficiency of 41.89%, and the specific cost of liquefied natural gas is 292.30 US$/GJ. It was verified that this cost increased along with electricity. The highest exergy destruction rates were obtained for Expander 1 and Air cooler 2. The highest average cost per exergy unit of fuel was obtained for the vertical separator, followed by Air coolers 1 and 2. An assessment of the exergoeconomic factor indicated that both expanders could benefit from a decrease in exergy destruction, improving the exergoeconomic performance of the overall system. Regarding the relative cost difference, all compressors presented high values and can be enhanced with low efforts.
Thermal Performance of Finned Heat Sinks Embedded with Form-Stable Myristic Acid Phase Change Material in Photovoltaic Cooling for Green Energy Storage
Authors: Munusamy Yamuna , Lin Onn John Wong , Alquraish Mohammed , Kchaou Mohamed , Sethupathi Sumathi
Published: October 2021

Photovoltaic (PV) panels must be equipped with a cooling system to increase their electrical output generation. Despite numerous publications on the fabrication of form-stable phase change material (FSPCM) for thermal energy storage application, studies on the usage of FSPCM for PV cooling are incredibly limited. In this work, the cooling performance of myristic acid FSPCM encapsulated with cross-linked nitrile rubber (NBR) was investigated. A fin heat sink (FHS) was employed to hold the FSPCM. The thermal performance of the FHS embedded with FSPCM (FHS-FSPCM) was preliminarily tested in an indoor setup. Results show that the FHS-FSPCM has a lower temperature distribution curve than the bare FHS, highlighting the increase in cooling capability of fabricated FSPCM. Field-testing of PV panels integrated with an FHS-FSPCM displayed that FSPCM manages to reduce the operating temperature of the panel by 4 to 15 °C and increase power output generation by 38.61%.
A Deterioration Diagnosis Circuit of a Lithium-Ion Battery Using Microcomputer Implementing Z-Transform Convolution
Authors: Yoshioka Naoyuki , Nagaoka Naoto
Published: October 2021

The deterioration of lithium-ion batteries has been detected by an increase in the battery impedance by means of an alternating current method or a battery capacity test. These methods require an interruption of the operation because the battery has to be removed. A method estimating equivalent circuit parameters of a lithium-ion battery during operation is proposed in this article. The increase in the internal impedance has a close relation to the deterioration of the battery. The circuit is expressed by a resister and an RC parallel circuit connected in series. The parameters can be estimated by applying a convolution technique to the voltage and current fluctuation of the battery during operation. A diagnosis circuit using a microcomputer is developed using a simple algorithm employing z-transformation in the parameter estimation. The estimated parameters depend on its state of charge (SOC) and ambient temperature. The SOC dependency is solved by estimating timing, and the temperature dependency is corrected by a function derived in this article. The deterioration diagnosis of the battery can be applied to a solar power generation system, and the feasibility is discussed in this article.
Opposite Tree-Tree Interactions Jointly Drive the Natural Fir Treeline Population on the Southeastern Tibetan Plateau
Authors: Wang Yafeng , Mao Qing , Ren Ping , Sigdel Shalik Ram
Published: October 2021

The long-term stability of alpine treeline positions and increased stem density are frequently reported by recent studies; however, whether a denser treeline forest is relevant to competitive tree–tree interactions remain unclear. Herein, we mapped and surveyed individual trees in two undisturbed Smith fir (Abies georgei var. smithii) treeline plots (with a size: 30 m × 200 m; plot NE1: 4477 m, NE2: 4451 m) near Ranwu Lake (RW) on the southeastern Tibetan Plateau. The surface pattern method and spatial point pattern analysis were used to detect the spatial distribution patterns of three size classes (seedlings, juveniles, adults) and spatial associations between the pairwise size classes. We also compared our results to the spatial patterns of the five other treeline forests (Deqin, Linzhi, Changdu, Yushu, Aba) reported from the Tibetan Plateau. Young trees dominated the two fir treeline plots. Both positive and negative spatial autocorrelations for all of the trees were detected in two study plots. Intraspecific facilitation and competition coexisted at the fir treelines in three forest regions (RW, Linzhi, Aba) characterized by a mild moist climate, whereas intraspecific facilitation dominated the other three forest regions (Changdu, Deqin, Yushu), which featured seasonal climatic stress or high disturbance pressure. Thus, increased stem density at alpine treeline can be linked to competitive interactions in relatively favorable environmental conditions. Overall, the spatial patterns of the treeline population are mainly shaped by the combination of thermal and moisture conditions and are also modulated by non-climatic variables (e.g., disturbance history and microtopography).
Color Change and Physical-Mechanical Properties of Polystyrene-Impregnated Glulam from Three Tropical Fast-Growing Wood Species
Authors: Hadi Yusuf Sudo , Hermawan Dede , Sulastiningsih Ignasia Maria , Basri Efrida , Pari Gustan , Pari Rohmah , Abdillah Imam Busyra
Published: October 2021

The aims of this work were to determine the color change and physical–mechanical properties of polystyrene glulam from three tropical wood species. Wood laminas were cut from logs harvested from a young plantation forest of manii (Maesopsis eminii), mangium (Acacia mangium), and rubber-wood (Hevea brasiliensis). The laminas were impregnated with monomer styrene that was polymerized using potassium peroxy-disulfate as a catalyst and heat. Three-layer glulam was constructed from the polystyrene laminas, using isocyanate glue and cold press. For comparison purposes, three-layer untreated glulam and solid wood samples were prepared. The results showed that the color change of polystyrene glulam was very small compared with untreated glulam. Polystyrene glulam had the highest density, while the density of untreated glulam did not differ from that of the solid wood. The moisture content of all products was matched to the environment, and fulfilled the Japanese standard. Compared with both types of glulams, solid wood had lower values for modulus of rupture (MOR), modulus of elasticity (MOE), and hardness, but higher shear strength. Meanwhile, polystyrene glulam had lower values for MOR and MOE, equal shear strength and wood failure, and higher hardness than the untreated glulam. All glulams had very little delamination in the hot water test. Only rubber-wood glulams fulfilled JAS 234-2003 for MOR, MOE, shear strength, and delamination. To obtain adequate physical–mechanical properties of glulams, medium-density wood is recommended for glulam manufacturing.
Residual Influence of Nitrogen, Phosphorus and Potassium Doses on Soil and Eucalyptus Nutrition in Coppice
Authors: Godoi Natasha Mirella Inhã , de Niro Gazola Rodolfo , Buzetti Salatiér , Jalal Arshad , de Souza Celestrino Thiago , da Silva Oliveira Carlos Eduardo , Nogueira Thiago Assis Rodrigues , Panosso Alan Rodrigo , Teixeira Filho Marcelo Carvalho Minhoto
Published: October 2021

The management of fertilizer is an important strategy for better nutrition and productivity of eucalyptus. Therefore, the objective of this research was to evaluate the isolated residual effect (carryover) of N, P and K fertilization on macro- and micronutrients in soil, leaf litter, leaf nutritional diagnosis and initial growth attributes of eucalyptus in a coppice system. Three experiments were carried out in a randomized block design with five replications. Experiment 1: four residual doses of N (0, 70, 105 and 140 kg ha−1) were applied as ammonium nitrate. Experiment 2: four residual doses of P2O5 (0, 40, 70 and 100 kg ha−1) were applied to plantations in furrows using triple superphosphate. Experiment 3: four residual K2O doses (0, 90, 135 and 180 kg ha−1) were applied as potassium chloride. The residual N doses did not influence leaf nutrient contents and initial growth of eucalyptus; however, increasing P residual doses increased soil P and Zn content, litter K content, decreased leaf Mg content, and increased initial growth (height and wood volume of eucalyptus). The residual K doses increased leaf litter K content and leaf Mn and Zn content but decreased leaf litter Ca, B and Fe and leaf Mg content. Residual potassium fertilization did not significantly influence the initial growth of eucalyptus in the Brazilian Cerrado.
Effect of Cold Plasma Treatment of Polymer Fibers on the Mechanical Behavior of Fiber-Reinforced Cementitious Composites
Authors: Thibodeaux Noah , Guerrero Daniel E. , Lopez Jose L. , Bandelt Matthew J. , Adams Matthew P.
Published: October 2021

Fiber-reinforced cementitious composites (FRCC) are a class of materials made by adding randomly distributed fibers to a cementitious matrix, providing better material toughness through the crack bridging behavior of the fibers. One of the primary concerns with FRCCs is the behavior of the fiber when a crack is formed. The fibers provide a stress-bridging mechanism, which is largely determined by the bond that exists between the concrete and the fiber’s outer surface. While many studies have determined the properties of FRCCs and potential benefits of using specific fiber types, the effects of low temperature or cold plasma treatment of polymer fibers on the mechanical behavior of the composite material are limited. Polymer fibers are notable for their low density, ductility, ease of manufacture, and cost-effectiveness. Despite these advantages, the surface properties of polymers do not enable the bonding potential given by steel or glass fibers when used in untreated FRCC, resulting in pull-out failures before the full displacement capacity of the fiber is utilized. For this reason, modification of the surface characteristics of polymer fibers can aid in higher bonding potential. Plasma treatment is a process wherein surfaces are modified through the kinetics of electrically charged and reactive species in a gaseous discharge environment. This paper is a preliminary study on the use of atmospheric pressure plasma generated at approximately room temperature. This atmospheric, cold plasma treatment is a method for improving the mechanical properties of FRCC using polymeric fibers. In this study, polypropylene and polyvinyl-alcohol fibers were cold plasma treated for 0, 30, 60, and 120 s before being used in cementitious mortar mixtures. Compression and flexure tests were performed using a displacement-based loading protocol to examine the impact of plasma treatment time on the corresponding mechanical performance of the fiber-reinforced cementitious composite. The experimental results obtained from this study indicate that there is a positive correlation between fiber treatment time and post-peak load-carrying capacity, especially for specimens subjected to flexural loading.
Impact of Thyme Microcapsules on Histamine Production by Proteus bacillus in Xinjiang Smoked Horsemeat Sausage
Authors: Yu Honghong , Huang Yali , Lu Liliang , Liu Yuhan , Tang Zonggui , Lu Shiling
Published: October 2021

Here, we explored the influences of thyme microcapsules on the growth, gene expression, and histamine accumulation by Proteus bacillus isolated from smoked horsemeat sausage. RT-qPCR was employed to evaluate the gene expression level of histidine decarboxylase (HDC) cascade-associated genes. We used HPLC to monitor histamine concentration both in pure culture as well as in the processing of smoked horsemeat sausage. Results showed that histamine accumulation was suppressed by thyme microcapsule inhibitory effect on the histamine-producing bacteria and the reduction in the transcription of hdcA and hdcP genes. Besides, compared with thyme essential oil (EO), thyme microcapsules exhibited higher antibacterial activity and had a higher score for overall acceptance. Therefore, the addition of thyme microcapsules in Xinjiang smoked horsemeat sausage inhibits histamine accumulation.
ABA and Bud Dormancy in Perennials: Current Knowledge and Future Perspective
Authors: Pan Wenqiang , Liang Jiahui , Sui Juanjuan , Li Jingru , Liu Chang , Xin Yin , Zhang Yanmin , Wang Shaokun , Zhao Yajie , Zhang Jie , Yi Mingfang , Gazzarrini Sonia , Wu Jian
Published: October 2021

Bud dormancy is an evolved trait that confers adaptation to harsh environments, and affects flower differentiation, crop yield and vegetative growth in perennials. ABA is a stress hormone and a major regulator of dormancy. Although the physiology of bud dormancy is complex, several advancements have been achieved in this field recently by using genetics, omics and bioinformatics methods. Here, we review the current knowledge on the role of ABA and environmental signals, as well as the interplay of other hormones and sucrose, in the regulation of this process. We also discuss emerging potential mechanisms in this physiological process, including epigenetic regulation.
Generalizability of GWA-Identified Genetic Risk Variants for Metabolic Traits to Populations from the Arabian Peninsula
Authors: Hebbar Prashantha , Abu-Farha Mohamed , Abubaker Jehad , Channanath Arshad Mohamed , Al-Mulla Fahd , Thanaraj Thangavel Alphonse
Published: October 2021

The Arabian Peninsula, located at the nexus of Africa, Europe, and Asia, was implicated in early human migration. The Arab population is characterized by consanguinity and endogamy leading to inbreeding. Global genome-wide association (GWA) studies on metabolic traits under-represent the Arab population. Replicability of GWA-identified association signals in the Arab population has not been satisfactorily explored. It is important to assess how well GWA-identified findings generalize if their clinical interpretations are to benefit the target population. Our recent study from Kuwait, which performed genome-wide imputation and meta-analysis, observed 304 (from 151 genes) of the 4746 GWA-identified metabolic risk variants replicable in the Arab population. A recent large GWA study from Qatar found replication of 30 GWA-identified lipid risk variants. These complementing studies from the Peninsula increase the confidence in generalizing metabolic risk loci to the Arab population. However, both the studies reported a low extent of transferability. In this review, we examine the observed low transferability in the context of differences in environment, genetic correlations (allele frequencies, linkage disequilibrium, effect sizes, and heritability), and phenotype variance. We emphasize the need for large-scale GWA studies on deeply phenotyped cohorts of at least 20,000 Arab individuals. The review further presents GWA-identified metabolic risk variants generalizable to the Arab population.
Signaling Pathways That Regulate Normal and Aberrant Red Blood Cell Development
Authors: Wilkes Mark C. , Shibuya Aya , Sakamoto Kathleen M.
Published: October 2021

Blood cell development is regulated through intrinsic gene regulation and local factors including the microenvironment and cytokines. The differentiation of hematopoietic stem and progenitor cells (HSPCs) into mature erythrocytes is dependent on these cytokines binding to and stimulating their cognate receptors and the signaling cascades they initiate. Many of these pathways include kinases that can diversify signals by phosphorylating multiple substrates and amplify signals by phosphorylating multiple copies of each substrate. Indeed, synthesis of many of these cytokines is regulated by a number of signaling pathways including phosphoinositide 3-kinase (PI3K)-, extracellular signal related kinases (ERK)-, and p38 kinase-dependent pathways. Therefore, kinases act both upstream and downstream of the erythropoiesis-regulating cytokines. While many of the cytokines are well characterized, the nuanced members of the network of kinases responsible for appropriate induction of, and response to, these cytokines remains poorly defined. Here, we will examine the kinase signaling cascades required for erythropoiesis and emphasize the importance, complexity, enormous amount remaining to be characterized, and therapeutic potential that will accompany our comprehensive understanding of the erythroid kinome in both healthy and diseased states.
Two-Scale Investigation of the Retention Behavior of a Well-Graded Mixed Soil
Authors: Bottiglieri Osvaldo , Cafaro Francesco , Cotecchia Federica
Published: October 2021

The hydraulic characterization of mixed compacted soils is helpful for the design of earthworks subjected to drying–wetting cycles. When the mixed soil is well-graded and made of both coarse and fine fractions, its matric suction may also be due to the short-range adsorption phenomena, as for the soil investigated in this research work. A silty–clayey sand was created by a mixing procedure and experimentally investigated at two different scales. Physical modeling of an infiltration process was performed, allowing an inverse numerical analysis to infer the water retention and the hydraulic conductivity functions of the soil, whereas element testing on soil specimens allowed direct determination of the same equations. In the article, problems related to the employed suction measurement techniques have been pointed out and discussed. By this two-scale combined strategy, features of the soil hydraulic behavior, such as the wetting collapse, the shrinkage during drying, and the loop of hysteresis, were also determined.
Do Eco-Friendly Floral Preservative Solutions Prolong Vase Life Better than Chemical Solutions?
Authors: Nguyen Toan Khac , Lim Jin Hee
Published: October 2021

Cut flowers have become an export income in the global floriculture market. They have multiple uses, such as for home beautification, in ceremonies (including weddings and funerals), and as symbols of love, appreciation, respect, etc., in humane society. Each type of cut flower has a different vase life and the longevity of their freshness is linked to preharvest, harvest, and postharvest tools and conditions. The postharvest quality and vase life must be considered in order to obtain the desirable qualities of cut flowers, and factors that affect this are important in the floral industry. The use of floral preservative solutions is good practice for prolonging the vase life of cut flowers. Currently, the eco-friendly solutions, which are used as floral preservatives for extending cut flower vase life, have been discovered to be a low-cost and organic alternative as compared to chemical solutions. However, there are certain problems associated with the use of chemical and eco-friendly solutions. In this review, we summarize several potential approaches to improve flower vase life and discuss the best choices for holding-preservative-solution practices.
Sulforaphane Causes Cell Cycle Arrest and Apoptosis in Human Glioblastoma U87MG and U373MG Cell Lines under Hypoxic Conditions
Authors: Sita Giulia , Graziosi Agnese , Hrelia Patrizia , Morroni Fabiana
Published: October 2021

Glioblastoma multiforme (GBM) is the most prevalent and aggressive primary brain tumor. The median survival rate from diagnosis ranges from 15 to 17 months because the tumor is resistant to most therapeutic strategies. GBM exhibits microvascular hyperplasia and pronounced necrosis triggered by hypoxia. Sulforaphane (SFN), an isothiocyanate derived from cruciferous vegetables, has already demonstrated the ability to inhibit cell proliferation, by provoking cell cycle arrest, and leading to apoptosis in many cell lines. In this study, we investigated the antineoplastic effects of SFN [20–80 μM for 48 h] in GBM cells under normoxic and hypoxic conditions. Cell viability assays, flow cytometry, and Western blot results revealed that SFN could induce apoptosis of GBM cells in a dose-dependent manner, under both conditions. In particular, SFN significantly induced caspase 3/7 activation and DNA fragmentation. Moreover, our results demonstrated that SFN suppressed GBM cells proliferation by arresting the cell cycle at the S-phase, also under hypoxic condition, and that these effects may be due in part to its ability to induce oxidative stress by reducing glutathione levels and to increase the phosphorylation of extracellular signal-regulated kinases (ERKs). Overall, we hypothesized that SFN treatment might serve as a potential therapeutic strategy, alone or in combination, against GBM.
Defective Uteroplacental Vascular Remodeling in Preeclampsia: Key Molecular Factors Leading to Long Term Cardiovascular Disease
Authors: Hong Kirim , Kim Soo Hyun , Cha Dong Hyun , Park Hee Jin
Published: October 2021

Preeclampsia is a complex hypertensive disorder in pregnancy which can be lethal and is responsible for more than 70,000 maternal deaths worldwide every year. Besides the higher risk of unfavorable obstetric outcomes in women with preeclampsia, another crucial aspect that needs to be considered is the association between preeclampsia and the postpartum cardiovascular health of the mother. Currently, preeclampsia is classified as one of the major risk factors of cardiovascular disease (CVD) in women, which doubles the risk of venous thromboembolic events, stroke, and ischemic heart disease. In order to comprehend the pathophysiology behind the linkage between preeclampsia and the development of postpartum CVD, a thorough understanding of the abnormal uteroplacental vascular remodeling in preeclampsia is essential. Therefore, this review aims to summarize the current knowledge of the defective process of spiral artery remodeling in preeclampsia and how the resulting placental damage leads to excessive angiogenic imbalance and systemic inflammation in long term CVD. Key molecular factors in the pathway—including novel findings of microRNAs—will be discussed with suggestions of future management strategies of preventing CVD in women with a history of preeclampsia.
Olive Varieties under UV-B Stress Show Distinct Responses in Terms of Antioxidant Machinery and Isoform/Activity of RubisCO
Authors: Piccini Chiara , Cai Giampiero , Dias Maria Celeste , Araújo Márcia , Parri Sara , Romi Marco , Faleri Claudia , Cantini Claudio
Published: October 2021

In recent decades, atmospheric pollution led to a progressive reduction of the ozone layer with a consequent increase in UV-B radiation. Despite the high adaptation of olive trees to the Mediterranean environment, the progressive increase of UV-B radiation is a risk factor for olive tree cultivation. It is therefore necessary to understand how high levels of UV-B radiation affect olive plants and to identify olive varieties which are better adapted. In this study we analyzed two Italian olive varieties subjected to chronic UV-B stress. We focused on the effects of UV-B radiation on RubisCO, in terms of quantity, enzymatic activity and isoform composition. In addition, we also analyzed changes in the activity of antioxidant enzymes (SOD, CAT, GPox) to get a comprehensive picture of the antioxidant system. We also evaluated the effects of UV-B on the enzyme sucrose synthase. The overall damage at biochemical level was also assessed by analyzing changes in Hsp70, a protein triggered under stress conditions. The results of this work indicate that the varieties (Giarraffa and Olivastra Seggianese) differ significantly in the use of specific antioxidant defense systems, as well as in the activity and isoform composition of RubisCO. Combined with a different use of sucrose synthase, the overall picture shows that Giarraffa optimized the use of GPox and opted for a targeted choice of RubisCO isoforms, in addition to managing the content of sucrose synthase, thereby saving energy during critical stress points.