bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved Innovation Robust Outliers Detection Method for Airborne Array Position and Orientation Measurement System
Authors: Junfang Bao , Jianli Li , Mengdi Wei , Chunyu Qu
Published: December 2022

The airborne array position and orientation measurement system (array POS) is a key device for high-resolution multi-dimensional real-time imaging motion compensation of military reconnaissance mapping. Abnormal values will appear in array POS inertial devices and measurement data in an environment of strong interference, which often leads to a decrease or even divergence in the combination accuracy. The existing detection methods based on innovation characteristics are only sensitive to measurement outliers, which are the abnormal data caused by the strong interference environment. In this paper, an improved innovation robust outliers detection method is proposed, which is valid for both measurement outliers and inertial device outliers. First, the improved outliers detection method based on the innovation of array POS is described. The gain matrix is adaptively adjusted by using the statistical characteristics of innovation. At the same time, the information distribution coefficient is adaptively adjusted by using the filtering performance of the sub filter, which realizes the detection and correction of measurement outliers. Then, the outlier detection method of inertial devices based on extrapolation prediction is added. The predicted value of the inertial device is extrapolated by the fourth-order difference method, and the outliers are recognized and eliminated by the adaptive threshold, which contributes to improving the robustness and accuracy of array POS. STD is selected in this paper to statistic the accuracy of array POS. Compared with the traditional federated Kalman filtering (KFK) methods, the accuracies of position, speed, heading angle and horizontal attitude angle of the left node and right node are all improved when there are outliers in the measurement data. Compared with the fault-tolerant federated combination method based on innovation characteristics, the accuracies of position, speed, heading angle and horizontal attitude angle of the left node and right node are all improved when there are abnormal values in the inertial device data.
Optimization of Characteristic Phenological Periods for Winter Wheat Extraction Using Remote Sensing in Plateau Valley Agricultural Areas in Hualong, China
Authors: Lv Shenghui , Xia Xingsheng , Pan Yaozhong
Published: December 2022

It is important to develop or validate remote sensing methods to explore agricultural management and food self-sufficiency in the agricultural areas of the Qinghai–Tibet Plateau under the influence of global change, ecological protection, and socio-economic development. Studies on the use of remote sensing to monitor crop planting on the Qinghai-Tibetan Plateau are limited, with inconclusive results. Therefore, in this study, we analyzed Sentinel-2A/B images and field survey data in Hualong, China (located in Hehuang Valley, Qinghai-Tibetan Plateau) for winter wheat identification and verification at different spatial scales based on the time series of the normalized difference phenology index (NDPI) and dynamic time warping (DTW) algorithm. The characteristic phenological period and the corresponding DTW threshold were optimized using remote sensing data extracted for winter wheat. The results showed that NDPI corresponding to the jointing-heading stage, grouting-harvesting stage, and jointing-harvesting stage with DTW could identify winter wheat regardless of whether the spatial scale was a single quadrat, a combination of two quadrats, or the entire study area. The NDPI corresponding to the jointing-heading stage (corresponding DTW threshold T = 0.158) could generate a relatively rational winter wheat map; the NDPI corresponding to the time series of the grouting-harvesting stage (combined with DTW threshold T = 0.195) could detect a planting area with relatively high accuracy when supported by cultivated land, which matches the statistical reporting of the winter wheat area data. Similarly, with the support of cultivated land data, the planted area could be identified early based on the phenological characteristics of winter wheat before overwintering; however, the extraction scheme needs to be optimized further.
Multi-Mission Satellite Detection and Tracking of October 2019 Sabiti Oil Spill in the Red Sea
Authors: Vankayalapati Koteswararao , Dasari Hari Prasad , Langodan Sabique , El Mohtar Samah , Sanikommu Sivareddy , Asfahani Khaled , Desamsetti Srinivas , Hoteit Ibrahim
Published: December 2022

A multi-mission satellite remote sensing (MSRS) approach is explored to detect and track leaked oil from the Sabiti oil tanker accident that occurred in the central Red Sea on 11 October 2019 (RSOS-2019). The spilled oil spread rapidly and reached the coastal land near Jeddah, the second largest city of KSA, on 17 October. Different oil spill detection algorithms were implemented on SAR and optical sensor-based satellite images to track the oil spill. Sentinel-1 SAR images were most efficient at detecting the spread and thickness of RSOS-2019, but their spatio-temporal coverage greatly limits their use for tracking the oil movement. The spread and propagation of oil were well captured by Sentinel-2 images up to three weeks after the accident day, in agreement with the SAR images. MODIS successfully detected the narrow patch of oil that was leaked on the incident day and the widespread oil patches two days after. Landsat-8 RGB composite and thermal infrared images captured the oil spill on 13 October. By filtering clouds from the Meteosat images through sequential analysis, the spread and movement of the oil patches were efficiently tracked on 13 October. PlanetScope images available between 12 and 17 October enabled tracking of the oil near the coastal waters. The inferred oil spill movements are consistent with the ocean currents as revealed by a high-resolution regional ocean reanalysis. Our results demonstrate the potential of the MSRS approach to detect and track oil spills in the open and coastal waters of the Red Sea in near real-time.
Analog Lock-In Amplifier Design Using Subsampling for Accuracy Enhancement in GMI Sensor Applications
Authors: Algueta-Miguel José M. , Beato-López J. Jesús , López-Martín Antonio J.
Published: December 2022

A frequency downscaling technique for enhancing the accuracy of analog lock-in amplifier (LIA) architectures in giant magneto-impedance (GMI) sensor applications is presented in this paper. As a proof of concept, the proposed method is applied to two different LIA topologies using, respectively, analog and switching-based multiplication for phase-sensitive detection. Specifically, the operation frequency of both the input and the reference signals of the phase-sensitive detector (PSD) block of the LIA is reduced through a subsampling process using sample-and-hold (SH) circuits. A frequency downscaling from 200 kHz, which is the optimal operating frequency of the employed GMI sensor, to 1 kHz has been performed. In this way, the proposed technique exploits the inherent advantages of analog signal multiplication at low frequencies, while the principle of operation of the PSD remains unaltered. The circuits were assembled using discrete components, and the frequency downscaling proposal was experimentally validated by comparing the measurement accuracy with the equivalent conventional circuits. The experimental results revealed that the error in the signal magnitude measurements was reduced by a factor of 8 in the case of the analog multipliers and by a factor of 21 when a PSD based on switched multipliers was used. The error in-phase detection using a two-phase LIA was also reduced by more than 25%.
Flexible SbSI/Polyurethane Nanocomposite for Sensing and Energy Harvesting
Authors: Nowacki Bartłomiej , Jała Jakub , Mistewicz Krystian , Przyłucki Roman , Kopeć Grzegorz , Stenzel Tomasz
Published: December 2022

The dynamic development of flexible wearable electronics creates new possibilities for the production and use of new types of sensors. Recently, polymer nanocomposites have gained great popularity in the fabrication of sensors. They possess both the mechanical advantages of polymers and the functional properties of nanomaterials. The main drawback of such systems is the complexity of their manufacturing. This article presents, for the first time, fabrication of an antimony sulfoiodide (SbSI) and polyurethane (PU) nanocomposite and its application as a piezoelectric nanogenerator for strain detection. The SbSI/PU nanocomposite was prepared using simple, fast, and efficient technology. It allowed the obtainment of a high amount of material without the need to apply complex chemical methods or material processing. The SbSI/PU nanocomposite exhibited high flexibility and durability. The microstructure and chemical composition of the prepared material were investigated using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS), respectively. These studies revealed a lack of defects in the material structure and relatively low agglomeration of nanowires. The piezoelectric response of SbSI/PU nanocomposite was measured by pressing the sample with a pneumatic actuator at different excitation frequencies. It is proposed that the developed nanocomposite can be introduced into the shoe sole in order to harvest energy from human body movement.
Evaluating Physical and Tactical Performance and Their Connection during Female Soccer Matches Using Global Positioning Systems
Authors: Errekagorri Ibai , Echeazarra Ibon , Olaizola Aratz , Castellano Julen
Published: December 2022

The objective of the present study was to evaluate the tactical and physical performance during official matches of a women’s soccer league and to correlate both dimensions in periods of 15 min. To do this, eight official matches of a semi-professional soccer team belonging to the Women’s Second Division of Spain (Reto Iberdrola) were analysed during the 2020–2021 season. The variables recorded were classified into two dimensions: tactical variables (i.e., Width, Length, Height and Surface Area) and physical variables (i.e., Total Distance Covered (TD), Total Distance Covered in High-Speed Running (HSR) and Total Distance Covered in Sprint). The main results were: (1) there were no differences between the periods in any of the tactical dimension variables; (2) in the physical dimension, a significant decrease in TD and HSR was described at the end of the match (period 60–75); and (3) some positive correlations were found among some variables of the tactical and physical dimension at the beginning and at the end of the match (periods 0–15, 60–75 and 75–90). The findings of the study suggest that connecting the tactical and physical dimension in the interpretation of team performance would allow for a better understanding of player and team performance and during competition.
Robust Trajectory and Resource Optimization in UAV-Enabled IoT Networks under Probabilistic LoS Channel in Presence of Jammers
Authors: Ji Zhi , Gao Yufang , Yang Wendong , Rong Chuanzhen
Published: December 2022

This paper studies the anti-jamming problem of unmanned aerial vehicle (UAV)-enabled Internet of Things (IoT) communication networks in the presence of a jammer under the accurate probabilistic line-of-sight (LoS) model. Our goal is to maximize the information collection throughput of the system under the assumption that only the jammer’s approximate location is known. To this end, we formulate a throughput maximization problem by optimizing the UAV trajectory, the IoT devices’ transmit power, and communication scheduling under the accurate real-time probabilistic LoS channel. However, the proposed optimization problem is non-convex and coupled, and hence intractable to be solved. In order to tackle the problem, a robust iterative algorithm is proposed by leveraging the block coordinate descent (BCD) method, the successive convex approximation (SCA) technology, the difference of convex (D.C) programming approach, and the S-procedure. Extensive simulation results show that our proposed algorithm significantly improves the system throughput while achieving a practical anti-jamming effect compared with the benchmark algorithms.
Design of a Low-Power and Low-Area 8-Bit Flash ADC Using a Double-Tail Comparator on 180 nm CMOS Process
Authors: Thai Hong-Hai , Pham Cong-Kha , Le Duc-Hung
Published: December 2022

This paper presents a low-area 8-bit flash ADC that consumes low power. The flash ADC includes four main blocks—an analog multiplexer (MUX), a comparator, an encoder, and an SPI (Serial Peripheral Interface) block. The MUX allows the selection between eight analog inputs. The comparator block contains a TIQ (Threshold Inverter Quantization) comparator, a control circuit, and a proposed architecture of a Double-Tail (DT) comparator. The advantage of using the DT comparator is to reduce the number of comparators by half, which helps reduce the design area. The SPI block can provide a simple way for the ADC to interface with microcontrollers. This mixed-signal circuitry is designed and simulated using 180 nm CMOS technology. The 8-bit flash ADC only employs 128 comparators. The applied input clock is 80 MHz, with the input voltage ranging from 0.6 V to 1.8 V. The comparator block outputs 127 bits of thermometer code and sends them to the encoder, which exports the seven least significant bits (LSB) of the binary code. The most significant bit (MSB) is decided by only one DT comparator. The design consumes 2.81 mW of power on average. The total area of the layout is 0.088 mm2. The figure of merit (FOM) is about 877 fJ/step. The research ends up with a fabricated chip with the design inserted into it.
Risk Contagion between Commodity Markets and the Macro Economy during COVID-19: Evidence from China
Authors: Shen Hong , Pan Qi
Published: December 2022

As the basic raw materials of economic activities, major commodities prices have a significant impact on the real economy. Due to the impact of the COVID-19 pandemic, major commodities prices have been fluctuating sharply in a “deep V” pattern since 2020. Therefore, accurately grasping the risk linkage between commodity markets and the macroeconomy is the key to preventing systemic risk and maintaining the smooth operation of the economy. Based on the MF-VAR model, this paper analyzed the risk contagion between China’s commodity markets and macroeconomic sectors from the perspective of volatility spillover, focusing on risk spillover and its dynamic evolution during the COVID-19 pandemic, and deeply analyzed the transmission mechanism of risk spillover based on the mixed-frequency causality test method. Our findings show that China’s commodity markets are the net exporter of risk contagion and that all macroeconomic sectors are the net recipient of risk contagion. During the period of COVID-19, the risk contagion effect was significantly intensified. The fluctuation of the commodity markets has a long-lasting negative impact on the investment sector and has caused changes in macroeconomic sectors, such as the reduction of medium- and long-term loans, the reduction of money circulation speed, and the weakening of micro-individual consumption willingness. The results of causality analysis show that wealth, interest rate, and expectation effects are present in the risk contagion between the commodity markets and macroeconomic sectors. While being directly or indirectly impacted by the commodity markets, each macroeconomic sector also generates adverse feedback to the commodity markets. The complete description of the risk contagion between the commodity markets and the macro economy has guiding significance for regulatory authorities to improve risk control policies and reinforce the macro regulatory system.
Green and Eco-Friendly Treatment of Textile Wastewater by Using Azadirachta indica Leaf Extract Combined with a Silver Nitrate Solution
Authors: Irshad Muhammad Atif , Humayoun Muhammad Ahmad , Al-Hussain Sami A. , Nawaz Rab , Arshad Muhammad , Irfan Ali , Zaki Magdi E. A.
Published: December 2022

The present study was conducted to treat textile industrial wastewater through the combination of green and synthetic solutions. Two case studies were applied for the treatment of wastewater. In the first case, discharged industrial effluent was reacted with Azadirachta Indica leaf extract solution for a 4 to 72 h retention time. After the reaction, some pollutants were treated but most required higher retention time and concentration of A. indica extract, which could be a potential adsorbent for wastewater treatment. In the second case, the discharged industrial effluent was reacted with A. indica solution with silver nitrate AgNO3 solution and was used as a treating agent for wastewater with a 4 to 72 h retention time. The second case was found to be better than the first case as it treated a greater number of pollutants. Moreover, treatment plant design feasibilities will be required for the application of findings of the present study on an industrial scale. This study can be useful to improve industrial estate’s environmental conditions for reducing pollution by industrial wastewater. There is also a need to raise environmental awareness regarding wastewater’s health effects in local communities.
Project Delivery Systems: The Partnering Concept in Integrated and Non-Integrated Construction Projects
Authors: Sari Endah Murtiana , Irawan Agustinus Purna , Wibowo Mochamad Agung , Siregar Januar Parlaungan , Praja Arief Kusuma Among
Published: December 2022

The project delivery system has a large effect in determining the quality of a project. Strategic plans determined by the owner in the project initiation phase must ensure that project performance indicators in the form of cost and quality as well as time are accomplished. A concept of partnering that is well-managed and planned from the initiation phase will determine the quality of the construction project. Increasing the maturity of partnering is needed in order to achieve better project performance indicators. The concept of partnering in integrated and non-integrated projects has a different pattern. This study intends to discuss the concept of partnering and then recommend several key strategies according to the project life cycle. Research this study is quantitative, analyzing secondary data in the form of weekly meetings and project reports with the comparative method and cause-and-effect analysis. The results show that in the phase above 51% of ongoing projects, there is a significant difference in the pattern of partnering between integrated and non-integrated projects. In order to improve deeper partnering, this research reveals several prerequisites that must be met in order to carry out effective partnering in non-integrated projects. This research may benefit owners, contractors, and stakeholders who want to develop their understanding and knowledge of the concepts of partnering and the maturity of partnering, which will be new strategies for developing and improving project delivery systems. This study focuses on a topic from the Sustainable Development Goals (SDGs), specifically partnership for the goal.
Impact of Fixed/Variable Speed Hydro, Wind, and Photovoltaic on Sub-Synchronous Torsional Oscillation—A Review
Authors: Mohale Vijay , Chelliah Thanga Raj
Published: December 2022

Series compensation is a cost-efficient way to enhance the system reliability and the power transfer capabilities of long transmission lines. As a result of series compensation, the sub-synchronous oscillation (SSO) causes a severe risk of torsional interactions (TI). Therefore, SSO becomes a serious risk factor in grid-integrated renewable energy systems. Numerous researchers have evaluated SSO instances in several types of asynchronous generators in power systems. In this paper, the categorization and the overview of the SSO phenomena have been vital for the different mechanisms, sophisticated systems, analytical techniques, and multiple reviews that have been propagated. This study provides SSO analysis for various types of renewable energy power plants. Finally, while dealing with conventional and new power systems, this study summarizes recent SSO-damping and alleviation techniques for practical perception and future perspectives.
Influence of Consumer Interaction and Community Relationships on Value Co-Creation Willingness: A Mediation Model of Chinese Sports Brands
Authors: Jiang Xiaowei , Mastromartino Brandon , Yang Qian , Zhang Jianwei , Zhang James J.
Published: December 2022

Existing research reveals the significance of understanding consumer interactions as an increasingly important determinant of sports consumption behaviors; yet, few studies have focused on the virtual communities of sporting goods brands, particularly for the Chinese marketplace that is becoming the largest globally. This study aimed to examine the relationships among consumer interaction, brand-community relationship, and consumer value co-creation willingness in the sports virtual brand communities of China. Research participants (n = 445) were consumers participating in online community activities of two leading sporting goods brands in China, Li-NING and Anta Sports. A questionnaire survey study was conducted. Regression analyses revealed that three out of four consumer interaction factors—cultural identity behavior, experiential communication behavior, and community maintenance behavior—exert a significant and positive impact on consumer value co-creation willingness. The strength of community relationship played a mediating role in these relationships. The other one, member screening interaction, did not find support. This study extends knowledge of sports brand marketing and management of virtual brand communities and recognizes the effectiveness of consumer value co-creation aspirations by highlighting the importance and reliance of customer-to-customer interaction and the strength of brand-community relationships.
Sustainable Non-Cooperative User Detection Techniques in 5G Communications for Smart City Users
Authors: Islam Shayla , Budati Anil Kumar , Hasan Mohammad Kamrul , Valiveti Hima Bindu , Vulupala Sridhar Reddy
Published: December 2022

The 4G network is not sufficient for achieving the high data requirements of smart city users. The 5G network intends to meet these requirements and overcome other application issues, such as fast data transmission, video buffering, and coverage issues, providing excellent mobile data services to smart city users. To allocate a channel or spectrum to a smart city user for error-free transmission with low latency, the accurate information of the spectrum should be detected. In this study, we determined the range of non-cooperative detection techniques, such as matched filter detection with inverse covariance approach (MFDI), cyclostationary feature detection with inverse covariance approach (CFDI), and hybrid filter detection with inverse covariance approach (HFDI); based on the results of these methods, we provided highly accurate spectrum information for smart city users, enabling sustainable development. To evaluate the performance of the proposed detection techniques, the following parameters are used: probability of detection (PD), probability of false alarms (Pfa), probability of miss detection (Pmd), sensing time, and throughput. The simulation results revealed that the HFDI detection method provided sustainable results at low signal-to-noise ratio ranges and improved channel detection and throughput of approximately 17% and 10%, respectively.
Practical Applications of Target Costing in a Multidisciplinary R&D Project
Authors: Kostrzewa-Nowak Dorota , Gos Waldemar
Published: December 2022

R&D requires expertise in the basic sciences, technical and technological knowledge, legal regulations and business, it seems necessary to enhance collaboration between researchers and businesses, especially small and medium-sized enterprises. In this paper, we present a case study of a collaboration between a university and a company in the implementation of R&D projects. The primary research methods used in this study comprised literature analysis, case study analysis, participant observation, direct observation, deductive reasoning, and the authors’ experience with prototype interview design, including telephone interviews (quantitative survey) and interviews with market experts and/or individuals responsible for specific processes in diagnostic and testing laboratories. The calculations presented for studied projects showed a large disproportion between the costs incurred for the production of prototypes and the selling price accepted by the market. However, this does not preclude profitability. Further analysis of the technological processes, materials, components, etc. should be carried out in order to point out the optimization measures and consequently to achieve the target profitability of the product. Conducting R&D works should take into account the task of commercialization. The use of the concept of target costing facilitates the initial assessment of project profitability and should be recommended when conducting R&D, especially at higher stages of technological readiness of the product. Projects involving a higher level of technological readiness should be carried out not only by people representing life sciences, technology, medicine, etc., but also by specialists in social sciences (e.g., accountants and marketing specialists).
Soft Budget Constraints in French Football through Public Financing of Stadiums
Authors: Moulard Jérémy , Lang Markus , Dermit-Richard Nadine
Published: December 2022

Several football stadiums were built or renovated in France for hosting the 2016 UEFA European Football Championship. This study examines to what extent financial support by local governments for stadium construction or renovation induces soft budget constraints (SBC) for professional sports clubs. We address the research question based on a quantitative case study in the context of the construction and renovation of eight football stadiums that took place in France between 2012 and 2016. Our data shows that the public sector financed on average 78% of the new stadiums’ total construction or renovation costs, and local governments paid on average 60% of the total annual rental costs. The results indicate that local governments in French professional football are “supporting organizations” and help to ensure the financial sustainability and viability of the clubs by allowing them to benefit from financial flexibility, which are typical characteristics of SBCs. In total, we identify 32 forms of public aid that we classified according to different categories of “softness” and whether these aids appeared ex ante or ex post. Public aid constituted financial support that was sometimes very substantial, amounting to several million euros in each case. This financial support is often not taken into account by the regulatory authorities and thus could be interpreted as hidden government subsidies to professional clubs, which in some cases exceeded the subsidy allowance of €2.3 million.
Thermally Radiative Darcy–Forchheimer Flow of Cu/Ag Nanoliquid in Water Past a Heated Stretchy Sheet with Magnetic and Viscous Dissipation Impacts
Authors: Divya S. , Alessa Nazek , Eswaramoorthi S. , Loganathan Karuppusamy
Published: December 2022

This communication predominately discusses the rheological attributes of the Darcy–Forchheimer flow of a nanoliquid over a stretchy sheet with a magnetic impact. The present model considers the two diverse nanoparticles, such as Cu and Ag, and water as a base liquid. The heat equation accounts for the consequences of thermal radiation and a nonlinear heat sink/source when evaluating heat transmission phenomena. The current mechanical system is represented by higher-order PDEs, which are then remodeled into nonlinear higher-order ODEs that employ appropriate symmetry variables. The current mathematical systems are numerically computed by implementing the bvp4c technique. The characteristic attitudes of the related pertinent factors on the non-dimensional profiles are sketched via the figures, tables, and charts. The analysis predicts that the speed of the nanoliquid particles becomes slower when there is more presence of a magnetic field and injection/suction parameters. The growing amount of radiation is also pointed out, and the Eckert number corresponds to enriching the thermal profile.
Decomposing Euler–Poincaré Flow on the Space of Hamiltonian Vector Fields
Authors: Esen Oğul , De Lucas Javier , Muñoz Cristina Sardon , Zając Marcin
Published: December 2022

The main result of this paper is a matched-pair decomposition of the space of symmetric contravariant tensors TQ. From this procedure two complementary Lie subalgebras of TQ under mutual interaction arise. Introducing a lift operator, the matched pair decomposition of the space of Hamiltonian vector fields is determined. According to this realization, the Euler–Poincaré flows on such spaces are decomposed into two subdynamics: one is the Euler–Poincaré formulation of isentropic fluid flows, and the other one corresponds with Euler–Poincaré equations on contravariant tensors of order n⩾2.
A New Design of a Terahertz Metamaterial Absorber for Gas Sensing Applications
Authors: Banerjee Sagnik , Dutta Purba , Basu Snehashish , Mishra Sunil Kumar , Appasani Bhargav , Nanda Sarita , Abdulkarim Yadgar I. , Muhammadsharif Fahmi F. , Dong Jian , Jha Amitkumar V. , Bizon Nicu , Thounthong Phatiphat
Published: December 2022

Metamaterial absorbers are used in the terahertz frequency regime as photo-detectors, as sensing elements, in imaging applications, etc. Narrowband absorbers, on account of their ultra-slender bandwidth within the terahertz frequency spectrum, show a significant shift in the absorption peak when an extrinsic entity relative to the absorber, like refractive index or temperature of the encircling medium, is altered. This property paves the path for the narrowband absorbers to be used as potential sensors to detect any alterations in the encircling medium. In this paper, a novel design of a terahertz metamaterial (MTM) absorber is proposed, which can sense the variations in the refractive index (RI) of the surrounding medium. The effective permeability of the structure is negative, while its permittivity is positive; thus, it is a μ-negative metamaterial. The layout involves a swastika-shaped design made of gold on top of a dielectric gallium arsenide (GaAs) substrate. The proposed absorber achieved a nearly perfect absorption of 99.65% at 2.905 terahertz (THz), resulting in a quality factor (Q-factor) of 145.25. The proposed design has a sensitivity of 2.12 THz/RIU over a range of varied refractive index from n = 1.00 to n = 1.05 with a step size of 0.005, thereby achieving a Figure of Merit (FoM) of 106. Furthermore, the sensor was found to have a polarization-insensitive characteristic. Considering its high sensitivity (S), the proposed sensor was further tested for gas sensing applications of harmful gases. As a case study, the sensor was used to detect chloroform. The proposed work can be the foundation for developing highly sensitive gas sensors.
A Conserved, Serine-Rich Protein Plays Opposite Roles in N-Mediated Immunity against TMV and N-Triggered Cell Death
Authors: Zhang Qingling , Wang Jubin , Zhang Xi , Deng Yingtian , Li Feng
Published: December 2022

Plant nucleotide-binding, leucine-rich, repeat-containing proteins (NLRs) play important roles in plant immunity. NLR expression and function are tightly regulated by multiple mechanisms. In this study, a conserved serine/arginine-rich protein (SR protein) was identified through the yeast one-hybrid screening of a tobacco cDNA library using DNA fragments from the N gene, an NLR that confers immunity to tobacco mosaic virus (TMV). This SR protein showed an interaction with a 3′ genomic regulatory sequence (GRS) and has a potential role in regulating the alternative splicing of N. Thus, it was named SR regulator for N, abbreviated SR4N. Further study showed that SR4N plays a positive role in N-mediated cell death but a negative role in N protein accumulation. SR4N also promotes multiple virus replications in co-expression experiments, and this enhancement may not function through RNA silencing suppression, as it did not enhance 35S-GFP expression in co-infiltration experiments. Bioinformatic and molecular studies revealed that SR4N belongs to the SR2Z subtype of the SR protein family, which was conserved in both dicots and monocots, and its roles in repressing viral immunity and triggering cell death were also conserved. Our study revealed new roles for SR2Z family proteins in plant immunity against viruses.
High Drug Resistance Levels Compromise the Control of HIV Infection in Pediatric and Adult Populations in Bata, Equatorial Guinea
Authors: Rodríguez-Galet Ana , Ventosa-Cubillo Judit , Bendomo Verónica , Eyene Manuel , Mikue-Owono Teresa , Nzang Jesús , Ncogo Policarpo , Gonzalez-Alba José María , Benito Agustín , Holguín África
Published: December 2022

A lack of HIV viral load (VL) and HIV drug resistance (HIVDR) monitoring in sub-Saharan Africa has led to an uncontrolled circulation of HIV-strains with drug resistance mutations (DRM), compromising antiretroviral therapy (ART). This study updates HIVDR data and HIV-1 variants in Equatorial Guinea (EG), providing the first data on children/adolescents in the country. From 2019–2020, 269 dried blood samples (DBS) were collected in Bata Regional Hospital (EG) from 187 adults (73 ART-naïve/114 ART-treated) and 82 children/adolescents (25 HIV-exposed-ART-naïve/57 ART-treated). HIV-1 infection was confirmed in Madrid by molecular/serological confirmatory tests and ART-failure by VL quantification. HIV-1 pol region was identified as transmitted/acquired DRM, predicted antiretroviral susceptibility (Stanfordv9.0) and HIV-1 variants (phylogeny). HIV infection was confirmed in 88.1% of the individuals and virological failure (VL > 1000 HIV-1-RNA copies/mL) in 84.2/88.9/61.9% of 169 ART-treated children/adolescents/adults. Among the 167 subjects with available data, 24.6% suffered a diagnostic delay. All 125 treated had experienced nucleoside retrotranscriptase inhibitors (NRTI); 95.2% were non-NRTI (NNRTI); 22.4% had experienced integrase inhibitors (INSTI); and 16% had experienced protease inhibitors (PI). At sampling, they had received 1 (37.6%), 2 (32%), 3 (24.8%) or 4 (5.6%) different ART-regimens. Among the 43 treated children–adolescents/37 adults with sequence, 62.8/64.9% carried viruses with major-DRM. Most harbored DRM to NNRTI (68.4/66.7%), NRTI (55.3/43.3%) or NRTI+NNRTI (50/33.3%). One adult and one child carried major-DRM to PI and none carried major-DRM to INSTI. Most participants were susceptible to INI and PI. DRM was absent in 36.2% of treated patients with VL > 1000 cp/mL, suggesting adherence failure. TDR prevalence in 59 ART-naïve adults was high (20.3%). One-half (53.9%) of the 141 subjects with pol sequence carried CRF02_AG. The observed high rate of ART-failure and transmitted/acquired HIVDR could compromise the 95-95-95-UNAIDS targets in EG. Routine VL and resistance monitoring implementation are mandatory for early detection of ART-failure and optimal rescue therapy selection ART regimens based on PI, and INSTI can improve HIV control in EG.
Cis-Allosteric Regulation of HIV-1 Reverse Transcriptase by Integrase
Authors: Masuda Takao , Kotani Osamu , Yokoyama Masaru , Abe Yuya , Kawai Gota , Sato Hironori
Published: December 2022

Reverse transcriptase (RT) and integrase (IN) are encoded tandemly in the pol genes of retroviruses. We reported recently that HIV-1 RT and IN need to be supplied as the pol precursor intermediates, in which RT and IN are in fusion form (RTIN) to exert efficient reverse transcription in the context of HIV-1 replication. The mechanism underlying RTIN’s effect, however, remains to be elucidated. In this study, we examined the effect of IN fusion on RT during reverse transcription by an in vitro cell-free assay, using recombinant HIV-1 RTIN (rRTIN). We found that, compared to recombinant RT (rRT), rRTIN generated significantly higher cDNAs under physiological concentrations of dNTPs (less than 10 μM), suggesting increased affinity of RTIN to dNTPs. Importantly, the cleavage of RTIN with HIV-1 protease reduced cDNA levels at a low dose of dNTPs. Similarly, sensitivities against RT inhibitors were significantly altered in RTIN form. Finally, analysis of molecular dynamics simulations of RT and RTIN suggested that IN can influence the structural dynamics of the RT active center and the inhibitor binding pockets in cis. Thus, we demonstrated, for the first time, the cis-allosteric regulatory roles of IN in RT structure and enzymatic activity.
Tidal Flushing Rather Than Non-Point Source Nitrogen Pollution Drives Nutrient Dynamics in A Putatively Eutrophic Estuary
Authors: Krause Johannes R. , Gannon Michelle E. , Oczkowski Autumn J. , Schwartz Morgan J. , Champlin Lena K. , Steinmann David , Maxwell-Doyle Martha , Pirl Emily , Allen Victoria , Burke Watson Elizabeth
Published: December 2022

The effects of nonpoint source nutrients on estuaries can be difficult to pinpoint, with researchers often using indicator species, monitoring, and models to detect influence and change. Here, we made stable isotope measurements of nitrogen and carbon in sediment, water column particulates, primary producers, and consumers at 35 stations in the reportedly eutrophic Barnegat Bay (New Jersey) to assess N sources and processing pathways. Combined with water quality and hydrological data, our C and N isoscapes revealed four distinct geographic zones with diverging isotopic baselines, indicating variable nutrient sources and processing pathways. Overall, the carbon stable isotopes (δ13C) reflected the terrestrial-marine gradient with the most depleted values in the urban and poorly flushed north of the estuary to the most enriched values in the salt marsh-dominated south. In contrast, the nitrogen stable isotope values (δ15N) were most enriched near the oceanic inlets and were consistent with offshore δ15N values in particulate organic matter. Several biogeochemical processes likely alter δ15N, but the relatively lower δ15N values associated with the most urbanized area indicate that anthropogenic runoff is not a dominant N source to this area. Our findings stand in contrast to previous studies of similar estuaries, as δ15N signatures of biota in this system are inversely correlated to population density and nutrient concentrations. Further, our analyses of archival plant (Spartina sp., Phragmites australis) and shell (Geukensia demissa, Ilyanassa obsoleta) samples collected between 1880 and 2020 indicated that δ15N values have decreased over time, particularly in the consumers. Overall, we find that water quality issues appear to be most acute in the poorly flushed parts of Barnegat Bay and emphasize the important role that oceanic exchange plays in water quality and associated estuarine food webs in the lagoon.
Understanding Drainage Dynamics and Irrigation Management in a Semi-Arid Mediterranean Basin
Authors: Altés Víctor , Bellvert Joaquim , Pascual Miquel , Villar Josep Maria
Published: December 2022

Irrigation is one of the main users of water worldwide and its overuse may affect the natural regimes of water systems. To avoid this, drainage and irrigation management needs to be improved. This study aims to determine the amount of water lost to drainage in a semi-arid Mediterranean irrigated area. Water use, rainfall and drainage were monitored for 12 months (2019–2020) in a 425 ha sub-basin in the Algerri-Balaguer irrigation district (8000 ha, NE Spain). In addition, irrigation requirements were estimated using the single-crop FAO-56 method and a two-source energy balance model (TSEB) was used to estimate actual evapotranspiration in the sub-basin. Water lost to drainage in the sub-basin was estimated as 18% of the total water that entered the perimeter as irrigation and rainfall, which are almost five time higher than theoretical requirements of leaching. Out of the total drainage water, 57% was estimated to be irrigation water and 43% rainwater. The average amount of irrigation water used was 614 mm and irrigation efficiency in the sub-basin was estimated at 80.2% and averaged actual evapotranspiration at 1144 mm. The available margin of improvement is between 19.3% of the present irrigation drainage ratio and the 3.8% estimated with the leaching requirement model.
Intermittent Rivers as a Challenge for Freshwater Ecosystems Quality Evaluation: A Study Case in the Ribeira de Silveirinhos, Portugal
Authors: Rodrigues Sara , Xavier Bárbara , Nogueira Sandra , Antunes Sara C.
Published: December 2022

Intermittent rivers and streams are aquatic ecosystems that lose hydrological connectivity during drought periods. Anthropogenic pressures combined with climate change accelerate the spatial and temporal intermittency of these ecosystems, promoting alterations in ecology and ecosystem functions. This study aimed to assess the ecological status of Ribeira de Silveirinhos, located in the municipalities of Valongo and Gondomar (north of Portugal), using the metrics described in the Water Framework Directive. Thus, five sampling sites were selected along Ribeira de Silveirinhos. Sampling was done in three different periods, spring of 2019 and 2020, and autumn of 2019. At each site, physical and chemical water parameters were measured, and the benthic macroinvertebrates community was characterized. Physical and chemical parameters showed low pH values at upstream sites (where the dry phase occurs and is surrounded by Eucalyptus monoculture) and high concentrations of phosphorus at the downstream sites (subjected to several anthropogenic activities, iron waters, and agriculture). The macroinvertebrate community revealed low values of specific abundance and richness, especially during the dry period. Sensitive taxa (Ephemeroptera, Plecoptera, and Trichoptera) were negatively correlated with flow intermittency. Results showed that Ribeira de Silveirinhos is classified between “poor” and “moderate” in terms of ecological status. Intermittent streams are undervalued, so their protection is at risk. Thus, it is important to consider the specific ecological functioning of these ecosystems and to adjust the planning and management models in order to guarantee ecological quality and conservation processes.
Investigation on Stall Characteristics of Centrifugal Pump with Guide Vanes
Authors: Ye Changliang , An Dongsen , Huang Wanru , Heng Yaguang , Zheng Yuan
Published: December 2022

Stall usually occurs in the hump area of the head curve, which will block the channel and aggravate the pump vibration. For centrifugal pumps with guide vanes usually have a clocking effect, the stall characteristic at different clocking positions should be focused. In this paper, the flow field of the centrifugal pump under stall conditions is numerically simulated, and the rotor–stator interaction effects of the centrifugal pump under stall conditions are studied. The double-hump characteristic is found in the head curve by using SAS (Scale Adaptive Simulation) model. The hump area close to the optimal working condition is caused by hydraulic loss, while the hump area far away from the optimal working condition point is caused by the combined action of Euler’s head and hydraulic loss. The SAS model can accurately calculate the wall friction loss, thus predicting the double-hump phenomenon. The pressure fluctuation and head characteristics at different clocking positions under stall conditions are obtained. It is found that when the guide vanes outlet in line with the volute tongue, the corresponding head is the highest, and the pressure fluctuation is the lowest. The mechanism of the clocking effect in the centrifugal pump with guide vanes is obtained by simplifying the hydrofoil. It is found that when the downstream hydrofoil leading edge is always interfered with by the upstream hydrofoil wake, the wake with low energy mixes the boundary layer with low energy, which causes small-pressure pulsation. The results could be used for the operation of centrifugal pumps with guide vanes.
Development Patterns of Fractured Water-Conducting Zones under Fully Mechanized Mining in Wet-Collapsible Loess Area
Authors: Teng Yonghai , Yi Sihai , Zhu Wei , Jing Shengqiang
Published: December 2022

The development pattern of fractured water-conducting zones (FWCZs) is closely related to mining safety and water conservation in mining areas. However, neither the development pattern nor the empirical formula in the prediction of the height of FWCZs are clear for fully mechanized caving mining conditions in wet collapsible loess areas. We took Lu’an Coal Mine as a case study, employing field measurements and numerical simulation to investigate surface subsidence and FWCZs. Under the conditions of fully mechanized top coal caving in thick coal seams, surface movement is more intense, and surface cracking is more frequent. Field measurements using boreholes indicated the ratio of fracture height to coal seam thickness was 19.1–23.4, and the ratio stays stable both by sliced fully mechanized mining and fully mechanized mining. The height of the FWCZ with fully mechanized mining is 1.37 times and 2.31 times larger than the height with sliced fully mechanized mining and ordinary mining, respectively. The numerical simulation by RFPA illustrated that the height of the FWCZ remained stable when it reached a certain rock level with the working face moving forward. Furthermore, we developed an empirical formula for predicating the maximum height of an FWCZ under fully mechanized mining conditions in wet collapsible loess areas. Finally, the research findings were applied in several coal mines to achieve safe production and water conservation. This work provides guidance for effectively mining safely and water conservation in similar geographic conditions.
A New Digital Twin for Climate Change Adaptation, Water Management, and Disaster Risk Reduction (HIP Digital Twin)
Authors: Henriksen Hans , Schneider Raphael , Koch Julian , Ondracek Maria , Troldborg Lars , Seidenfaden Ida , Kragh Søren , Bøgh Eva , Stisen Simon
Published: December 2022

The paper analyzes the national DK-model hydrological information and prediction (HIP) system and HIP portal viewed as a ‘digital twin’ and how the introduction of real-time dynamic updating of the DK-model HIP simulations can make room for plug-in submodels with real-time boundary conditions made available from an HIP portal. The possible feedback to a national real-time risk knowledge base during extreme events (flooding and drought) is also discussed. Under climate change conditions, Denmark is likely to experience more rain in winter, more evapotranspiration in summer, intensified cloudbursts, drought, and sea level rise. These challenges were addressed as part of the Joint Governmental Digitalization Strategy 2016–2020 for better use and sharing of public data about the terrain, water, and climate to support climate adaptation, water management, and disaster risk reduction. This initiative included the development of a new web-based data portal (HIP portal) developed by the Danish Agency for Data Supply and Infrastructure (SDFI). GEUS delivered 5 terabytes of hydrological model data to the portal, with robust calibration methods and hybrid machine learning (ML) being key parts of the deliverables. This paper discusses the challenges and potentials of further developing the HIP digital twin with ‘plug-in digital twins’ for local river basins, including feedback to the national level.