bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding the Experiences of Fulbright Visiting Scholars—A Qualitative Systematic Review
Authors: Lally Marisa
Published: January 2022

The Fulbright Program funds approximately 850 visiting scholars to the United States each year from over 100 countries. This study aimed to understand how the experiences of Fulbright visiting scholars are represented in education literature and beyond. This study used thematic analysis methods for a systematic review to examine relevant literature from the past 10 years (2011–2021). The study found that the experiences of scholars visiting Fulbright shape their academic lives in their home countries and their complex attitudes toward the United States, but their experiences are unique and depend on the geopolitical relationship between the United States and their home countries.
The Unrepeatable Human Mind—Challenges in the Development of Cognitive Information Systems—What Makes a Machine Human?
Authors: Mattyasovszky-Philipp Dóra , Putnoki Attila Márton , Molnár Bálint
Published: January 2022

The understanding of human cognition has not been fully achieved; therefore, Information Systems (IS) are not yet fully synchronized with humans. By understanding the cognition process, we will be able to create a human-tailored Cognitive Information Systems (CISs). The necessity for this research is supported by the fact that present business decision makers are faced with challenges that they cannot solve in the time available without CIS. Here, the aim of the authors is to underpin the adaptability of cognitive resonance and the role of the info-communication via Human–Computer Interaction (HCI)—including linkage, relation and impacts, showing the needed direction to increase the effectiveness of the Human–Computer Interaction (HCI), that leads to an improved CIS building with a higher cognitive level. The applied research methodology consists of research analyses and an assessment of the available publications to pursue a comparative study pattern; then, a model building paradigm has been used for observing and monitoring the work with a CIS during HCI. We found a huge gap regarding information processing in the recent literature, that has been caused by the wide range of interdisciplinarity. Our research approach provides an overview of how other disciplines influence HCI and how the human mental model is supported with value added.
A Methodological Approach to the Teaching STEM Skills in Latin America through Educational Robotics for School Teachers
Authors: Cano Sandra
Published: January 2022

The study aims to design a methodological approach that allows educational robotics to develop STEM competences for schoolteachers, but with a gender focus. The phases within consist of designing a set of workshops with a gender approach, making use of Arduino, as it allows for introducing concepts in electronics and programming. For this, a mixed research method was applied, where quantitative and qualitative information was collected. The study was carried out with teachers from Latin American schools, where teachers from Chile and Colombia participated the most, and was conducted in virtual mode through the Zoom platform. As a result, it was found that Arduino and its components can be used to build projects that can be related in a real context, which further motivates students. It was also found that the levels of creativity, attitude, and motivation of the students increased with the workshops that were carried out.
Differentiated Protection and Hot/Cold-Aware Data Placement Policies through k-Means Clustering Analysis for 3D-NAND SSDs
Authors: Son Seungwoo , Kim Jaeho
Published: January 2022

3D-NAND flash memory provides high capacity per unit area by stacking 2D-NAND cells having a planar structure. However, because of the nature of the lamination process, the frequency of error occurrence varies depending on each layer or physical cell location. This phenomenon becomes more pronounced as the number of flash memory write/erase (Program/Erasure) operations increases. Error correction code (ECC) is used for error correction in the majority of flash-based storage devices, such as SSDs (Solid State Drive). As this method provides a constant level of data protection for all-flash memory pages, there is a limitation in 3D-NAND flash memory, where the error rate varies depending on physical location. Consequently, in this paper, pages and layers with varying error rates are classified into clusters using the k-means machine-learning algorithm, and each cluster is assigned a different level of data protection strength. We classify pages and layers based on the number of error occurrences measured at the end of the endurance test, and for areas vulnerable to errors, it is shown as an example of providing differentiated data protection strength by adding parity data to the stripe. Furthermore, areas vulnerable to retention errors are identified based on retention error rates, and bit error rates are significantly reduced through our hot/cold-aware data placement policy. We show that the proposed differential data protection and hot/cold-aware data placement policies improve the reliability and lifespan of 3D-NAND flash memory compared with the existing ECC- or RAID-type data protection scheme.
Usability and Security Testing of Online Links: A Framework for Click-Through Rate Prediction Using Deep Learning
Authors: Damaševičius Robertas , Zailskaitė-Jakštė Ligita
Published: January 2022

The user, usage, and usability (3U’s) are three principal constituents for cyber security. The effective analysis of the 3U data using artificial intelligence (AI) techniques allows to deduce valuable observations, which allow domain experts to design practical strategies to alleviate cyberattacks and ensure decision support. Many internet applications, such as internet advertising and recommendation systems, rely on click-through rate (CTR) prediction to anticipate the possibility that a user would click on an ad or product, which is key for understanding human online behaviour. However, online systems are prone to click on fraud attacks. We propose a Human-Centric Cyber Security (HCCS) model that additionally includes AI techniques targeted at the key elements of user, usage, and usability. As a case study, we analyse a CTR prediction task, using deep learning methods (factorization machines) to predict online fraud through clickbait. The results of experiments on a real-world benchmark Avazu dataset show that the proposed approach outpaces (AUC is 0.8062) other CTR forecasting approaches, demonstrating the viability of the proposed framework.
Rate Maximization in a UAV Based Full-Duplex Multi-User Communication Network Using Multi-Objective Optimization
Authors: Hashir Syed Muhammad , Gupta Sabyasachi , Megson Gavin , Aryafar Ehsan , Camp Joseph
Published: January 2022

In this paper, we study an unmanned-aerial-vehicle (UAV) based full-duplex (FD) multi-user communication network, where a UAV is deployed as a multiple-input–multiple-output (MIMO) FD base station (BS) to serve multiple FD users on the ground. We propose a multi-objective optimization framework which considers two desirable objective functions, namely sum uplink (UL) rate maximization and sum downlink (DL) rate maximization while providing quality-of-service to all the users in the communication network. A novel resource allocation multi-objective-optimization-problem (MOOP) is designed which optimizes the downlink beamformer, the beamwidth angle, and the 3D position of the UAV, and also the UL power of the FD users. The formulated MOOP is a non-convex problem which is generally intractable. To handle the MOOP, a weighted Tchebycheff method is proposed, which converts the problem to the single-objective-optimization-problem (SOOP). Further, an alternative optimization approach is used, where SOOP is converted in to multiple sub-problems and optimization variables are operated alternatively. The numerical results show a trade-off region between sum UL and sum DL rate, and also validate that the considered FD system provides substantial improvement over traditional HD systems.
Multiple Dielectric-Supported Ridge-Loaded Rhombus-Shaped Wideband Meander-Line Slow-Wave Structure for a V-Band TWT
Authors: Wang Yuxin , Dong Yang , Zhu Xiangbao , Guo Jingyu , Xu Duo , Wang Shaomeng , Gong Yubin
Published: January 2022

A multiple dielectric-supported ridge-loaded rhombus-shaped meander-line (MDSRL-RSML) slow-wave structure (SWS) is proposed for a V-band wideband traveling wave tube (TWT). The high-frequency and transmission characteristics of the SWS are investigated. The proposed structure can realize stable output via attenuator and special phase-velocity jumping. Particle-in-cell (PIC) results indicate that, for a 7 kV, 0.1 A sheet-beam, the average output power can reach 60 W at 60 GHz and a 3 dB bandwidth of 9 GHz, with the corresponding gain and electron efficiency of 30.8 dB and 17.2%, respectively. Compared with the dielectric-supported rhombus-shape meander-line (DS-RSML) SWS, the proposed structure has a wider bandwidth, higher gain, more stable structure, and better heat dissipation ability, which make it a good candidate source in millimeter-wave communications.
Cascaded RLS Adaptive Filters Based on a Kronecker Product Decomposition
Authors: Rusu Alexandru-George , Ciochină Silviu , Paleologu Constantin , Benesty Jacob
Published: January 2022

The multilinear system framework allows for the exploitation of the system identification problem from different perspectives in the context of various applications, such as nonlinear acoustic echo cancellation, multi-party audio conferencing, and video conferencing, in which the system could be modeled through parallel or cascaded filters. In this paper, we introduce different memoryless and memory structures that are described from a bilinear perspective. Following the memory structures, we develop the multilinear recursive least-squares algorithm by considering the Kronecker product decomposition concept. We have performed a set of simulations in the context of echo cancellation, aiming both long length impulse responses and the reverberation effect.
Home Energy Forecast Performance Tool for Smart Living Services Suppliers under an Energy 4.0 and CPS Framework
Authors: Rodrigues Filipe Martins , Cardeira Carlos , Calado João M. F. , Melicio Rui
Published: January 2022

Industry 4.0 is a paradigm consisting of cyber-physical systems based on the interconnection between all sorts of machines, sensors, and actuators, generally known as things. The combination of energy technology and information and technology communication (ICT) enables measurement, control, and automation to be performed across the distributed grid with high time resolution. Through digital revolution in the energy sector, the term Energy 4.0 emerges in the future electric sector. The growth outlook for appliance usage is increasing and the appearance of renewable energy sources on the electric grid requires strategies to control demand and peak loads. Potential feedback for energy performance is the use of smart meters in conjunction with smart energy management; well-designed applications will successfully inform, engage, empower, and motivate consumers. This paper presents several hands-on tools for load forecasting, comparing previous works and verifying which show the best energy forecasting performance in a smart monitoring system. Simulations were performed based on forecasting of the hours ahead of the load for several households. Special attention was given to the accuracy of the forecasting model for weekdays and weekends. The development of the proposed methods, based on artificial neural networks (ANN), provides more reliable forecasting for a few hours ahead and peak loads.
A Redesign Methodology to Improve the Performance of a Thermal Energy Storage with Phase Change Materials: A Numerical Approach
Authors: Harris Bernal Itamar A. , James Rivas Arthur M. , Ortega Del Rosario María De Los A. , Saghir M. Ziad
Published: January 2022

In recent years, phase change materials (PCMs) have been presented as a suitable alternative for thermal energy storage (TES) systems for solar water heater (SWH) applications. However, PCMs’ low thermal conductivity and the high dependence on external conditions are the main challenges during the design of TES systems with PCMs. Design actions to improve the performance of the TES systems are crucial to achieve the necessary stored/released thermal energy and guarantee the all-day operation of SWHs under specific system requirements. In this study, a TES with PCM in the configuration of a heat exchanger was redesigned, focused on achieving two main targets: an outlet water temperature over 43 °C during discharging time (15 h) and efficiency over 60% to supply the hot water demand of two families (400 L). A four-step redesign methodology was proposed and implemented through numerical simulations to address this aim. It was concluded that the type, encapsulation shape, and amount of PCM slightly impacted the system’s performance; however, selecting a suitable sensible heat storage material had the highest impact on meeting the system’s targets. The redesigned TES reached 15 operating hours with a minimum outlet water temperature of 45.30 °C and efficiency of 76.08%.
Energy Transition Planning with High Penetration of Variable Renewable Energy in Developing Countries: The Case of the Bolivian Interconnected Power System
Authors: Navia Marco , Orellana Renan , Zaráte Sulmayra , Villazón Mauricio , Balderrama Sergio , Quoilin Sylvain
Published: January 2022

The transition to a more environmentally friendly energy matrix by reducing fossil fuel usage has become one of the most important goals to control climate change. Variable renewable energy sources (VRES) are a central low-carbon alternative. Nevertheless, their variability and low predictability can negatively affect the operation of power systems. On this issue, energy-system-modeling tools have played a fundamental role. When exploring the behavior of the power system against different levels of VRES penetration through them, it is possible to determine certain operational and planning strategies to balance the variations, reduce the operational uncertainty, and increase the supply reliability. In many developing countries, the lack of such proper tools accounting for these effects hinders the deployment potential of VRES. This paper presents a particular energy system model focused on the case of Bolivia. The model manages a database gathered with the relevant parameters of the Bolivian power system currently in operation and those in a portfolio scheduled until 2025. From this database, what-if scenarios are constructed allowing us to expose the Bolivian power system to a set of alternatives regarding VRES penetration and Hydro storage for that same year. The scope is to quantify the VRES integration potential and therefore the capacity of the country to leapfrog to a cleaner and more cost-effective energy system. To that aim, the unit-commitment and dispatch optimization problem are tackled through a Mixed Integer Linear Program (MILP) that solves the cost objective function within its constraints through the branch-and-cut method for each scenario. The results are evaluated and compared in terms of energy balancing, transmission grid capability, curtailment, thermal generation displacement, hydro storage contribution, and energy generation cost. In the results, it was found that the proposed system can reduce the average electricity cost down to 0.22 EUR/MWh and also reduce up to 2.22 × 106 t (96%) of the CO2 emissions by 2025 with very high penetration of VRES but at the expense of significant amount of curtailment. This is achieved by increasing the VRES installed capacity to 10,142 MW. As a consequence, up to 7.07 TWh (97%) of thermal generation is displaced with up to 8.84 TWh (75%) of load covered by VRES.
Reply to Diesendorf, M. Comment on “Seibert, M.K.; Rees, W.E. Through the Eye of a Needle: An Eco-Heterodox Perspective on the Renewable Energy Transition. Energies 2021, 14, 4508”
Authors: Seibert Megan K. , Rees William E.
Published: January 2022

When we published Seibert and Rees (2021) [...]
Torsional Deformation Analysis of Large Miter Gate under Different Operating Conditions
Authors: Li Ran , Xiao Hanbin , Xiao Xinyi , Zhang Jie , Pan Lin
Published: January 2022

As an important part of the navigation facilities for water conservancy and electricity in Gezhouba, the operation safety of herringbone gates is critical. Due to the minor torsional stiffness of the gate, it is easy to produce torsional deformation during operating under the water pressure, wind load, and gravity, which may lead to fatigue damage. In this study, a gate model with a combination of plate unit and the solid unit was developed, taking a ship lock herringbone gate as an example. According to the gate load under different working conditions, such as self-weight, surge, etc., in this research, we used the finite element analysis software ANSYS to analyze and calculate the stress and strain of the gate, with and without a back tie, and obtained the characteristics of the gate torsional deformation under various working conditions. The results show that the gate’s deformation degree and the direction under different working conditions vary greatly. The maximum deformation point mostly appears in the upper or lower corners of the oblique joint column. The gate deformation can be significantly reduced by adding the back tie. The research results provide a theoretical basis for further optimizing the design of the gate and installation of the back tie to reduce the fatigue damage of the miter gate.
Multistage Optimization toward a Nearly Net Zero Energy Building Due to Climate Change
Authors: Aram Kimiya , Taherkhani Roohollah , Šimelytė Agnė
Published: January 2022

Climate change is one of the major problems of the planet. The atmosphere is overloaded with carbon dioxide caused by fossil fuels that are burned for energy. Almost 40 percent of the total energy worldwide is used by the building sector, which comes from non-renewable sources and contributes up to 30% of annual greenhouse gas emissions globally. The building sector in Iran accounts for 33.8% of Iran’s total energy usage. Within the building sector, the energy consumption of Iranian educational buildings is 2.5 times higher than educational buildings in developed countries. One of the most effective ways of reducing global energy consumption and greenhouse gas emissions is retrofitting existing buildings. This study aims to investigate whether a particular energy-optimized design under the present climate conditions would respond effectively to future climate change. This can help designers make a better decision on an optimal model, which can remain optimal over the years based on climate change. For methodological purposes, multistage optimization was used to retrofit an existing educational building. Specifically, the non-dominated sorting genetic algorithm (NSGA-II) was chosen to minimize the cooling and heating load, as well as consider investment costs for present and future weather files, using the jEPlus tool. Furthermore, the TOPSIS method was used to identify the best set of retrofit measures. For this purpose, a four-story educational building in Tehran was modeled on Design Builder software v7.0.0.116 as a case study to provide a better understanding for researchers of how to effectively retrofit a building to achieve a nearly zero energy building considering climate change. The results show that the optimized solution for the present weather file does not remain the optimized solution in 2080. Moreover, it is shown that to have an optimized building in regard to future weather files, the model should be designed for the future weather conditions. This study shows that if the building becomes optimized using the present weather file the total energy consumption will be reduced by 65.14% and 86.18% if using the future weather file. These two figures are obtained by implementing active and passive measures and show the priority of using the future weather file for designers. Using PV panels also, this building is capable of becoming a nearly net zero building, which would produce about 90% of its own energy demands.
Model Predictive Control Based Path Tracking and Velocity Control with Rollover Prevention Function for Autonomous Electric Road Sweeper
Authors: Jeong Yonghwan , Kim Wongun , Yim Seongjin
Published: January 2022

This paper presents a model predictive control (MPC)-based algorithm for rollover prevention of an autonomous electric road sweeper (AERS). For AERS, the basic function of autonomous driving is a path- and velocity-tracking control needed to make a vehicle follow given path and velocity profiles. On the other, the AERS adopts an articulated frame steering (AFS) mechanism which can make cornering behavior agile. Moreover, the tread of the AERS is narrow, and the height of the mass center is high. As a result, it is prone to roll over. For this reason, it is necessary to design a controller for path and velocity tracking and rollover prevention in order to improve maneuverability and roll safety of the AERS. A kinematic model was adopted as a vehicle one for the AERS. With the vehicle model, reference states of position and velocity were determined that are needed to make the AERS track the reference path and prevent rollover. With the vehicle model and reference states, an MPC-based motion controller was designed to optimize articulation angle and velocity commands. The load-transfer ratio (LTR) was used to measure a rollover propensity. To evaluate the proposed algorithm, a simulation was conducted for the U-turn scenario. Simulation results show that the proposed algorithm improves path tracking and prevents the rollover of the AERS.
Research on Module Layout and Module Coverage of an Automobile Exhaust Thermoelectric Power Generation System
Authors: Zhou Weiqi , Yang Jiasheng , Qin Qing , Zhu Jiahao , Xu Shiyu , Luo Ding , Wang Ruochen
Published: January 2022

Due to the low efficiency of thermoelectric generators (TEGs), many scholars have focused on the structural optimization of TEGs rather than on the optimization of the layout of thermoelectric modules. We aimed to investigate the effect of module layout on the output power of an automotive exhaust thermoelectric power generation system. The module spacing and module coverage ratio were compared under different working conditions based on a numerical simulation. The results show that, under high-temperature conditions, when the module spacing expands from 5 mm to 35 mm, the output power growth rate of modules of different sizes ranges between 8% and 9%. Moreover, under low-temperature conditions, a high coverage ratio of modules will not increase the total output power but, instead, make it decline. In fact, choosing a larger-size module can improve the temperature uniformity, thereby increasing the output power of the automotive thermoelectric power generation system. Hence, the present study has verified that, under different working conditions, different module layouts and module coverage ratios have an impact on the output power of the thermoelectric power generation system, which sheds new light on the improvement of automotive thermoelectric power generation systems.
Implementation of Dynamic Controls for Grid-Tied-Inverters through Next-Generation Smart Meters and Its Application in Modernized Grid
Authors: Sharma Navonita , Chakraborty Ajoy Kumar
Published: January 2022

In this paper, an introduction and comprehensive analysis have been presented for the implementation and application of modern smart meters which include Unbundled Smart Meters (USM) and Next-Generation Open Real-Time Smart Meters (NORM). This article also contributes to methods through which USM and NORM could provide a better perspective to the already available technologies for grid-tied-inverter controlled feeding renewables to the grid. The research proposes a next-generation smart meter model with the feature of a phasor measurement unit. The meter is further integrated with a controller board that controls the power injection from the inverter to the grid based on the real-time data obtained from the smart meter. The inverter is simulated with an open-circuit fault and is controlled to provide non-oscillatory power to the grid based on an instantaneous grid power factor or phase requirement. The proposed meter has the flexibility to add additional features to control the inverter based on other grid requirements such as active and reactive power control, tariff implementation, etc. This manuscript provides the analytical aspects of the use of smart meters in efficient energy management and also addresses the need for smart technologies for grid modernization.
Digitalize the Twin: A Method for Calibration of Reference Data for Transfer Real-World Test Drives into Simulation
Authors: Holder Martin , Elster Lukas , Winner Hermann
Published: January 2022

In the course of the development of automated driving, there has been increasing interest in obtaining ground truth information from sensor recordings and transferring road traffic scenarios to simulations. The quality of the “ground truth” annotation is dictated by its accuracy. This paper presents a method for calibrating the accuracy of ground truth in practical applications in the automotive context. With an exemplary measurement device, we show that the proclaimed accuracy of the device is not always reached. However, test repetitions show deviations, resulting in non-uniform reliability and limited trustworthiness of the reference measurement. A similar result can be observed when reproducing the trajectory in the simulation environment: the exact reproduction of the driven trajectory does not always succeed in the simulation environment shown as an example because deviations occur. This is particularly relevant for making sensor-specific features such as material reflectivities for lidar and radar quantifiable in dynamic cases.
A Study of the Pyrolysis Products of Kraft Lignin
Authors: Borella Matteo , Casazza Alessandro A. , Garbarino Gabriella , Riani Paola , Busca Guido
Published: January 2022

In order to valorize lignin wastes to produce useful aromatic compounds, the thermal degradation pyrolysis of Kraft lignin in the absence of catalysts has been investigated at 350, 450, and 550 °C. The high content of sulfur in the fresh sample led to the formation of S-containing compounds in products whose evolution in the gas phase was monitored through GC-MS analysis. Pyrolytic gas is rich in CH4, CO, CO2, and H2S with the presence of other sulfur compounds in smaller amounts (i.e., CH3SH, CH3-S-CH3, SO2, COS, and CS2). Biochar morphology and elemental composition have been investigated by means of SEM and EDX. The carbon content reaches ~90% after pyrolysis at 550 °C, while the oxygen content showed a decreasing trend with increasing temperature. From GC-MS analysis, bio-oil resulted rich in alkyl-alkoxy phenols, together with (alkyl)dihydroxy benzenes and minor amounts of hydrocarbons and sulfur compounds. NaOH/H2O and EtOH/H2O extraction were performed with the aim of extracting phenolic-like compounds. Sodium hydroxide solution allowed a better but still incomplete extraction of phenolic compounds, leaving a bio-oil richer in sulfur.
Wind and Sea Breeze Characteristics for the Offshore Wind Farms in the Central Coastal Area of Taiwan
Authors: Cheng Ke-Sheng , Ho Cheng-Yu , Teng Jen-Hsin
Published: January 2022

Renewable energy is crucial for achieving net zero emissions. Taiwan has abundant wind resources and most major wind farms are offshore over the Taiwan Strait due to a lack of space on land. A thorough study that includes time series modeling of wind speed and sea breeze identification and evaluation for Taiwan’s offshore wind farms was conducted. The time series modeling identified two periodic (annual and diurnal) components and an autoregressive model for multiple-year wind speed time series. A new method for sea breeze type identification and magnitude evaluation is proposed. The method (named as EACH) utilizes a vector and an ellipse to represent the wind condition of a day. Verification of the type identification determined by the new method in two cases of different seasons has been conducted by using surface weather charts and wind data measured by lidar. It is a concise, effective, and programmable way to filter a number of dates for type identification and speed change precursor of sea breeze. We found that the typical daily wind power production of corkscrew sea breeze in Central Taiwan is more than 33 times that of pure sea breeze and more than 9 times that of backdoor sea breeze, which highlights the impact of sea breeze types on wind power.
Fault Diagnosis Method for MMC-HVDC Based on Bi-GRU Neural Network
Authors: Wang Yanting , Zheng Dingkun , Jia Rong
Published: January 2022

The Modular Multilevel Converter-High Voltage Direct Current (MMC-HVDC) system is recognized worldwide as a highly efficient strategy for transporting renewable energy across regions. As most of the MMC-HVDC system electronics are weak against overcurrent, protections of the MMC-HVDC system are the major focus of research. Because of the insufficiencies of the conventioned fault diagnosis method of MMC-HVDC system, such as hand-designed fault thresholds and complex data pre-processing, this paper proposes a new method for fault detection and location based on Bidirectional Gated Recurrent Unit (Bi-GRU). The proposed method has obvious advantages of feature extraction on the bi-directional structure, and it simplifies the pre-processing of fault data. The simplified pre-processing avoids the loss of valid information in the data and helps to extract detailed fault characteristics, thus improving the accuracy of the method. Extensive simulation experiments show that the proposed method meets the speed requirement of MMC-HVDC protections (2 ms) and the accuracy rate reaches 99.9994%. In addition, the method is not affected by noise and has a high potential for practical applications.
Inclusion and Withdrawal Criteria for Growth Hormone (GH) Therapy in Children with Idiopathic GH Deficiency—Towards Following the Evidence but Still with Unresolved Problems
Authors: Smyczyńska Joanna
Published: January 2022

According to current guidelines, growth hormone (GH) therapy is strongly recommended in children and adolescents with GH deficiency (GHD) in order to accelerate growth rate and attain normal adult height. The diagnosis of GHD requires demonstration of decreased GH secretion in stimulation tests, below the established threshold value. Currently, GHD in children is classified as secondary insulin-like growth factor-1 (IGF-1) deficiency. Most children diagnosed with isolated GHD present with normal GH secretion at the attainment of near-final height or even in mid-puberty. The most important clinical problems, related to the diagnosis of isolated GHD in children and to optimal duration of rhGH therapy include: arbitrary definition of subnormal GH peak in stimulation tests, disregarding factors influencing GH secretion, insufficient diagnostic accuracy and poor reproducibility of GH stimulation tests, discrepancies between spontaneous and stimulated GH secretion, clinical entity of neurosecretory dysfunction, discrepancies between IGF-1 concentrations and results of GH stimulation tests, significance of IGF-1 deficiency for the diagnosis of GHD, and a need for validation IGF-1 reference ranges. Many of these issues have remained unresolved for 25 years or even longer. It seems that finding solutions to them should optimize diagnostics and therapy of children with short stature.
Phenotypic Plasticity of Cunninghamialanceolata (Lamb.) Hook. Seedlings in Response to Varied Light Quality Treatments
Authors: Liu Qingqing , Huang Zhijun , Ma Xiangqing , Tigabu Mulualem , Xing Xianshuang , Jin Shaofei , Liu Bo
Published: January 2022

Effects of light quality on phenotypic plasticity in Cunninghamialanceolata (Lamb.) Hook. seedlings during growth and development, and the underlying mechanisms, were investigated. The seedlings showed distinct morphological adjustments when exposed to an equal photosynthetic photon flux density (400 μmol·m−2·s−1) of different light qualities: monochromatic blue (BL), monochromatic red (RL), monochromatic far-red (FrL), mixed RL and FrL at 1:1 (RFr1:1L), mixed RL and FrL at 1:2 (RFr1:2L), and multi-wavelength white (WL, control). Compared with WL, FrL and BL significantly promoted height increment. However, BL was unfavorable for root growth. The seedling biomass was lower and the root-to-shoot ratio was smaller under BL. RL promoted leaf area enlargement, root growth, axillary bud number, and increased the root-to-shoot ratio, but inhibited stem elongation. Low R/Fr ratios or increased FrL proportion increased seedling stem elongation. The seedling growth under RFr1:1L treatment was poorer than that under other treatments; however, the number of axillary buds was the highest. The plasticity of leaf morphology traits was lower in different treatments, and that of axillary bud traits was crucial in the adaptation of C. lanceolata to light quality. Precise management of light quality and wavelength in controlled environments may maximize the economic efficiency of forest production and enhance its quality.
Forest Structure and Composition Are Critical to Hurricane Mortality
Authors: Zhang Jiaying , Heartsill-Scalley Tamara , Bras Rafael L.
Published: January 2022

Hurricanes can cause severe damage to tropical forests. To understand the nature of hurricane impacts, we analyze and compare immediate effects from category-4 hurricane María in 2017 and category-3 hurricane Hugo in 1989 at Bisley Experimental Watersheds (BEW) in the Luquillo Experimental Forest, Puerto Rico. We show that hurricane María caused lower mortality than hurricane Hugo, even though hurricane María was a stronger event with higher sustained wind. The lower mortality was due to the combination of lower accumulated cyclone energy at the site and more wind-resistant forest structure and composition at the time of disturbance. We compare our study site with a nearby location that has the same forest type, Luquillo Forest Dynamics Plot (LFDP), and describe the similarities and differences of mortality and impact factors between the two sites during the two events. During hurricane Hugo, LFDP experienced much lower mortality than BEW, even though the accumulated cyclone energy at LFDP was higher. The difference in mortality was due to contrasting forest structure and composition of the two sites. Our results demonstrate that forest structure and composition at the time of the disturbance were more critical to hurricane-induced mortality at the two sites than accumulated cyclone energy.
Influence of Fermentation Conditions (Temperature and Time) on the Physicochemical Properties and Bacteria Microbiota of Amasi
Authors: Maleke Mpho , Doorsamy Wesley , Abrahams Adrian Mark , Adefisoye Martins Ajibade , Masenya Kedibone , Adebo Oluwafemi Ayodeji
Published: January 2022

The aim of this present study was to optimize the fermentation conditions (time and temperature) of amasi (a Southern African fermented dairy product) using response surface methodology (RSM), and to determine the physicochemical properties, as well as the microbial composition, using next generation sequencing. Fermentation time and temperature were optimized to produce different amasi samples and different parameters, including pH, total soluble solids (TSS), total titratable acids (TTA), and consistency. All the variables studied were found to show significant (p ≤ 0.05) changes with increasing fermentation time and temperature. Numerical optimization was used to obtain the optimal fermentation conditions for amasi; based on RSM, it was 32 °C for 140 h, while with k-means clustering, it was 25 °C for 120 h. Under both conditions for the optimal samples, the pH reduced from 6.64 to 3.99, TTA increased from 0.02 to 0.11 (% lactic acid), TSS decreased from 9.47 to 6.67 °Brix, and the consistency decreased from 23 to 15.23 cm/min. Most of the identified bacteria were linked to lactic acid bacteria, with the family Lactobacillaceae being the most predominant in amasi, while in raw milk, Prevotellaceae was the most abundant. The fermentation conditions (time and temperature) had a significant influence on the parameters investigated in this study. Results of this study could provide information for the commercialization of quality amasi.
Analysis of Tip Clearance Effect on the Transportation Characteristics of a Multiphase Rotodynamic Pump Based on the Non-Uniform Bubble Model
Authors: Sun Weihua , Yu Zhiyi , Zhang Ke , Liu Zheng
Published: January 2022

The multiphase rotodynamic pump is widely used in petroleum and gas exploitation, and blade tip clearance may cause flow instability and performance deterioration. In the present work, the influence of tip clearance on the transportation characteristic in a multiphase rotodynamic pump is investigated based on the non-uniform bubble model, in which the bubbles’ coalescence and break-up are considered. The influence mechanism of tip clearance on the energy performance is revealed. The results show that the leakage flow rate increases linearly with the increase in tip clearance, but variation in pump energy performance shows the opposite trend. In addition, a larger tip clearance results in a sharply decreased pressure increment in the impeller, while in the guide vane, the increment is raised slightly. For the 0 mm tip clearance condition, a positive vortex (relative to the impeller rotation direction) is observed in the impeller passage. However, the opposite leakage vortex is also found in the region near the tip clearance when the tip clearance is considered, and the vortex strength increases for a larger tip clearance.
Phytochemical Profile, Biological Properties, and Food Applications of the Medicinal Plant Syzygium cumini
Authors: Qamar Muhammad , Akhtar Saeed , Ismail Tariq , Wahid Muqeet , Abbas Malik Waseem , Mubarak Mohammad S. , Yuan Ye , Barnard Ross T. , Ziora Zyta M. , Esatbeyoglu Tuba
Published: January 2022

Syzygium cumini, locally known as Jamun in Asia, is a fruit-bearing crop belonging to the Myrtaceae family. This study aims to summarize the most recent literature related to botany, traditional applications, phytochemical ingredients, pharmacological activities, nutrition, and potential food applications of S. cumini. Traditionally, S. cumini has been utilized to combat diabetes and dysentery, and it is given to females with a history of abortions. Anatomical parts of S. cumini exhibit therapeutic potentials including antioxidant, anti-inflammatory, analgesic, antipyretic, antimalarial, anticancer, and antidiabetic activities attributed to the presence of various primary and secondary metabolites such as carbohydrates, proteins, amino acids, alkaloids, flavonoids (i.e., quercetin, myricetin, kaempferol), phenolic acids (gallic acid, caffeic acid, ellagic acid) and anthocyanins (delphinidin-3,5-O-diglucoside, petunidin-3,5-O-diglucoside, malvidin-3,5-O-diglucoside). Different fruit parts of S. cumini have been employed to enhance the nutritional and overall quality of jams, jellies, wines, and fermented products. Today, S. cumini is also used in edible films. So, we believe that S. cumini’s anatomical parts, extracts, and isolated compounds can be used in the food industry with applications in food packaging and as food additives. Future research should focus on the isolation and purification of compounds from S. cumini to treat various disorders. More importantly, clinical trials are required to develop low-cost medications with a low therapeutic index.
A Slow Single-Species Model with Non-Symmetric Variation of the Coefficients
Authors: Alharbi Fahad M.
Published: January 2022

A single-species population model exhibiting a symmetric slow variation for the carrying capacity and intrinsic growth rate is evaluated explicitly. However, it is unrealistic to eliminate the possibility of a clear separation in the evolution of the biotic environmental elements; thus, this paper considers the situation where these elements have a hierarchical variation on the time scales. Accordingly, two particular situations are recognized, which are the carrying capacity varies faster than the growth rate and vice versa. Applying the multi-time scaling technique in such a system provides a small parameter, which leads us to construct analytical approximate expressions for the population behavior, using the perturbation approach. Such approximations display very good agreement with the numerical simulations.
Structural Stability of Coalitions: A Formal Model Highlighting the Role of Participants Positioned between Members and Neutral Actors
Authors: Monsuur Herman , Janssen René H. P.
Published: January 2022

Given a fixed network that links various actors, we introduce a formal model that describes the structural stability of coalitions. To this end, we used the partition of the set of all actors in three distinct positions: members, i.e., those who are central to a coalition; participants, i.e., those who are not actively engaged with the issues at hand; neutral actors, i.e., non-members, those who are not party to any interests and outside the coalition. Using the language of networks, we formulated three assumptions that may be used to characterize the stability of this partition. We paid particular attention to the role of participants as they facilitate or complicate extensions of a given coalition. Given the fixed network, we (1) illustrate the verification of the stability of a coalition, (2) provide existence results of stable coalitions, and (3) set the limits to their credible extensions. Our three formal assumptions may serve as a platform for discussions regarding the stability of coalitions.
A Study on Gel/Space Ratio Development in Binary Mixture Containing Portland Cement and Meta-Illite Calcined Clay/Rice Husk Ash
Authors: Nduka David O. , Olawuyi Babatunde J. , Joshua Opeyemi O. , Omuh Ignatius O.
Published: January 2022

Supplementary cementitious materials (SCMs) have been widely used to enhance both the microscopic and macroscopic properties of the Portland cement (PC)–SCM composite matrix. Few studies have been undertaken to establish the gel/space ratio of meta-illite calcined clay (MCC) and rice husk ash (RHA)-based high-performance concrete (HPC) mortar. This experimental paper describes a conventional degree of hydration (non-evaporable water) and porosity routes of establishing a link amid the gel/space ratio and compressive strength of a sieved mortar from Class 1 (50–75 MPa) HPC at an early age. Using the non-evaporable water method, this paper predicted the gel/space ratio of the hardened MCC/RHA-based HPC mortars and curved fitted into Powers’ exponent equation. The results from this study revealed that MCC or RHA additions (5–30% by weight of PC) to the PC-SCM matrix led to a moderate decline in the compressive strength of the low water-binder ratio (W/B) HPC mortar. The modification aimed at void volume (superabsorbent polymers, SAP, and air) applying Bolomey’s formula and Powers’ gel/space ratio developed a suitable fitting into the Powers’ model. This experimental procedure shows feasibility to predict the MCC and RHA outcome on the compressive strength of HPC.
f = m*a: A Framework for Investigating the Regulation of Replication Timing
Authors: Rhind Nicholas
Published: January 2022

Stochastic models of replication timing posit that origin firing timing is regulated by origin firing probability, with early-firing origins having a high probability of firing and late-firing origins having a lower probability. However, they offer no insight into why one origin should have a higher firing probability than another. Here, a simple framework is suggested for how to approach the question by noting that the firing probability (f) must be the product of the stoichiometry of the MCM replicative helicase loaded at the origin (m) and the probability with which that MCM is activated (a). This framework emphasizes that mechanistic understanding of replication timing must focus on MCM loading and activation and can be simplified to the equation f = m*a.
SPECC1L Mutations Are Not Common in Sporadic Cases of Opitz G/BBB Syndrome
Authors: Migliore Chiara , Vendramin Anna , McKee Shane , Prontera Paolo , Faravelli Francesca , Sachdev Rani , Dias Patricia , Mascaro Martina , Licastro Danilo , Meroni Germana
Published: January 2022

Opitz G/BBB syndrome (OS) is a rare genetic developmental condition characterized by congenital defects along the midline of the body. The main clinical signs are represented by hypertelorism, laryngo–tracheo–esophageal defects and hypospadias. The X-linked form of the disease is associated with mutations in the MID1 gene located in Xp22 whereas mutations in the SPECC1L gene in 22q11 have been linked to few cases of the autosomal dominant form of this disorder, as well as to other genetic syndromes. In this study, we have undertaken a mutation screening of the SPECC1L gene in samples of sporadic OS cases in which mutations in the MID1 gene were excluded. The heterozygous missense variants identified are already reported in variant databases raising the issue of their pathogenetic meaning. Recently, it was reported that some clinical manifestations peculiar to OS signs are not observed in patients carrying mutations in the SPECC1L gene, leading to the proposal of the designation of ‘SPECC1L syndrome’ to refer to this disorder. Our study confirms that patients with diagnosis of OS, mainly characterized by the presence of hypospadias and laryngo–tracheo–esophageal defects, do not carry pathogenic SPECC1L mutations. In addition, SPECC1L syndrome-associated mutations are clustered in two specific domains of the protein, whereas the missense variants detected in our work lies elsewhere and the impact of these variants in the function of this protein is difficult to ascertain with the current knowledge and will require further investigations. Nonetheless, our study provides further insight into the SPECC1L syndrome classification.
Genomic Diversity Profiling and Breed-Specific Evolutionary Signatures of Selection in Arunachali Yak
Authors: Kour Aneet , Niranjan Saket Kumar , Malayaperumal Mohan , Surati Utsav , Pukhrambam Martina , Sivalingam Jayakumar , Kumar Amod , Sarkar Mihir
Published: January 2022

Arunachali yak, the only registered yak breed of India, is crucial for the economic sustainability of pastoralist Monpa community. This study intended to determine the genomic diversity and to identify signatures of selection in the breed. Previously available double digest restriction-site associated DNA (ddRAD) sequencing data of Arunachali yak animals was processed and 99,919 SNPs were considered for further analysis. The genomic diversity profiled based on nucleotide diversity, π (π = 0.041 in 200 bp windows), effective population size, Ne (Ne = 83) and Runs of homozygosity (ROH) (predominance of shorter length ROHs) was found to be optimum. Subsequently, 207 regions were identified to be under selective sweeps through de-correlated composite of multiple signals (DCMS) statistic which combined three individual test statistics viz. π, Tajima’s D and |iHS| in non-overlapping 100 kb windows. Mapping of these regions revealed 611 protein-coding genes including KIT, KITLG, CDH12, FGG, FGA, FGB, PDGFRA, PEAR1, STXBP3, olfactory receptor genes (OR5K3, OR5H6 and OR1E1) and taste receptor genes (TAS2R1, TAS2R3 and TAS2R4). Functional annotation highlighted that biological processes like platelet aggregation and sensory perception were the most overrepresented and the associated regions could be considered as breed-specific signatures of selection in Arunachali yak. These findings point towards evolutionary role of natural selection in environmental adaptation of Arunachali yak population and provide useful insights for pursuing genome-wide association studies in future.