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Tao, Da, Haibo Tan, Hailiang Wang, Xu Zhang, Xingda Qu y Tingru Zhang. "A Systematic Review of Physiological Measures of Mental Workload". International Journal of Environmental Research and Public Health 16, n.º 15 (30 de julio de 2019): 2716. http://dx.doi.org/10.3390/ijerph16152716.
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Mental workload (MWL) can affect human performance and is considered critical in the design and evaluation of complex human-machine systems. While numerous physiological measures are used to assess MWL, there appears no consensus on their validity as effective agents of MWL. This study was conducted to provide a comprehensive understanding of the use of physiological measures of MWL and to synthesize empirical evidence on the validity of the measures to discriminate changes in MWL. A systematical literature search was conducted with four electronic databases for empirical studies measuring MWL with physiological measures. Ninety-one studies were included for analysis. We identified 78 physiological measures, which were distributed in cardiovascular, eye movement, electroencephalogram (EEG), respiration, electromyogram (EMG) and skin categories. Cardiovascular, eye movement and EEG measures were the most widely used across varied research domains, with 76%, 66%, and 71% of times reported a significant association with MWL, respectively. While most physiological measures were found to be able to discriminate changes in MWL, they were not universally valid in all task scenarios. The use of physiological measures and their validity for MWL assessment also varied across different research domains. Our study offers insights into the understanding and selection of appropriate physiological measures for MWL assessment in varied human-machine systems.
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Mun, Ji-Sun y Sung-Phil Mun. "Structural and Thermal Characterization of Milled Wood Lignin from Bamboo (Phyllostachys pubescens) Grown in Korea". Molecules 29, n.º 1 (28 de diciembre de 2023): 183. http://dx.doi.org/10.3390/molecules29010183.
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The structural and thermal characterization of milled wood lignin (MWL) prepared from bamboo (Phyllostachys pubescens) grown in Korea was investigated, and the results were compared with bamboo MWLs from other studies. The C9 formula of the bamboo MWL was C9H7.76O3.23N0.02 (OCH3)1.41. The Mw and Mn of MWL were 13,000 and 4400 Da, respectively, which resulted in a polydispersity index (PDI) of 3.0. The PDI of the prepared MWL was higher than other bamboo MWLs (1.3–2.2), suggesting a broader molecular weight distribution. The structural features of MWL were elucidated using FT-IR spectroscopy and NMR techniques (1H, 13C, HSQC, 31P NMR), which indicate that MWL is of the HGS-type lignin. The major lignin linkages (β-O-4, β-β, β-5) were not different from other bamboo MWLs. The syringyl/guaiacyl ratio, determined from 1H NMR, was calculated as 0.89. 31P NMR revealed variations in hydroxyl content, with a higher aliphatic hydroxyl content in MWL compared to other bamboo MWLs. Thermal properties were investigated through TGA, DSC, and pyrolysis-GC/MS spectrometry (Py-GC/MS). The DTGmax of MWL under inert conditions was 287 °C, and the Tg of MWL was 159 °C. Py-GC/MS at 675 °C revealed a syringyl, guaiacyl, p-hydroxyphenyl composition of 17:37:47.
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Li, Wenchao. "Word length distribution of Japanese dialects". International Journal of Quantitative and Qualitative Research Methods 10, n.º 1 (15 de enero de 2022): 1–16. http://dx.doi.org/10.37745/ijqqrm.13/vol10n1716.
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This study applies a mathematical linguistic approach to explore word length distribution of Japanese dialects to cluster dialects at a lexical level. Data were extracted from spoken recordings of native speakers from 47 areas. The findings revealed that the further south the area was, the longer the mean word length (MWL) became. In majority of dialects, MWL ranges from one to nine. The Saga dialect has the longest MWL (3.26). Further analysis of the MWL-frequency relationship via the Altmann-fitter reveals that MWL-frequency of all dialects fit more than 30 distribution models, including the binomial and Poisson families.
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Xu, Miaomiao, Chao Wang, Gaojin Lyu, Lei Zhong, Liyuan Yang, Zhiwei Wang, Chengrong Qin et al. "Structural Characterization and Antioxidant Activity of Milled Wood Lignin from Xylose Residue and Corncob". Polymers 11, n.º 12 (13 de diciembre de 2019): 2092. http://dx.doi.org/10.3390/polym11122092.
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Xylose residue (XR), after diluted acid treatment of corncob, consists of cellulose and lignin. However, structural changes of XR lignin have not been investigated comprehensively, and this has seriously hindered the efficient utilization of lignin. In this study, corncob milled wood lignin (CC MWL), and xylose residue milled wood lignin (XR MWL) were isolated according to the modified milled wood lignin (MWL) method. The structural features of two lignin fractions were thoroughly investigated via fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and two dimensional nuclear magnetic resonance (2D NMR) spectroscopy techniques. XR MWL with higher yield and lower bound carbohydrate contents presented more phenolic OH contents than CC MWL due to partial cleavage of β-O-4. Furthermore, the molecular weights of XR MWL were increased, possibly because of condensation of the lignin during the xylose production. A study on antioxidant activity showed that XR lignin had better radical scavenging ability than that of 2,6-Di-tert-butyl-4-methyl-phenol (BHT) and CC MWL. The results suggested that the lignin in xylose residue, showing great antioxidant properties, has potential applications in food additives.
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Saphier, Nicole, Jessica Kondraciuk, Elizabeth Morris, Blanca Bernard-Davila y Victoria Mango. "Preoperative Localization of Breast MRI Lesions: MRI-guided Marker Placement With Radioactive Seed Localization as an Alternative to MRI-guided Wire Localization". Journal of Breast Imaging 2, n.º 3 (23 de abril de 2020): 250–58. http://dx.doi.org/10.1093/jbi/wbaa012.
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Abstract Objective Preoperative MRI-guided wire localization (MWL) presents challenges to both the physician and patient. In this study, we examined the efficiency and outcome of MRI-guided marker placement followed by mammographic-guided radioactive seed localization (MMP/RSL) as an alternative localization method. The primary outcome parameter was pathology upon excision. The secondary outcome parameters were total procedure time and clinical indication for localization. Methods A retrospective review of a large tertiary cancer center’s breast imaging database was performed. Records of 21 patients with MMP/RSL (24 markers) from August 2013 to January 2019 were compared with 34 patients receiving MWL (48 wires) from January 2016 to January 2019. Multiple factors, including age, prelocalization pathology, postsurgical pathology, concordance, re-excision rates, and total procedure time required for each technique, were compared. Univariate and descriptive statistical analyses were performed. Results Mean patient age in years (MMP/RSL = 54.1 ± 13.1, MWL = 55.1 ± 10.8, P = 0.389), time in MR scanner in minutes (MMP/RSL = 31.7 ± 12.0, MWL = 35.8 ± 13.1, P = 0.678), and postsurgical pathology malignancy rates (MMP/RSL = 71.4%, MWL = 65.7%, P = 0.7715) were similar without statistically significant differences. As expected, the mean total procedure time was slightly longer without a statistically significant difference (47.3 ± 19.8 min versus 35.8 ± 13.1 min, P = 0.922) for the MMP/RSL group. All patients in both groups underwent successful localization with 100% radiologic-pathology concordance. Re-excision rates were lower for the MMP/RSL group (9.5%) versus the MWL group (16.7%); however, they were not found to be statistically significant (P = 0.7104). Conclusion MMP/RSL is a feasible alternative to MWL and may alleviate many challenges presented by MWL. Further studies are needed.
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Pouliou, Anna, Fotini Kehagia, Georgios Poulios, Magdalini Pitsiava-Latinopoulou y Evangelos Bekiaris. "Drivers’ Reaction Time and Mental Workload: A Driving Simulation Study". Transport and Telecommunication Journal 24, n.º 4 (1 de noviembre de 2023): 397–408. http://dx.doi.org/10.2478/ttj-2023-0031.
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Abstract Drivers play a significant role in causing serious accidents, which underscores the need for further investigating the human element in order to improve road safety. Given the predominance of the information processing approach in driver’s behavior research field, an important psychological construct, Mental Workload (MWL), has been introduced to study the behavior of drivers. The objective of this paper is to investigate the impact of increased MWL on driver behavior and specifically the changes in driver’s Reaction Time (RT) under increased MWL. The experiment conducted in the driving simulator of the Hellenic Institute of Transport which is part of the Centre for Research and Technology Hellas, with the participation of 56 subjects from all age groups. For the simulation of the increased MWL conditions during driving, a secondary task was employed. To this end, the MIT AgeLab Delayed Digit Recall Task in the 1-back version was adapted for the needs of the present research. The driving scenario included 4 unexpected events, which further increase driver’s MWL. Driving performance was observed and relative parameters were measured as RT on the unexpected events, accidents occurred, and maneuvers performed. Appropriate statistical analysis was performed to examine the difference in the drivers’ RT in the unexpected events. Results demonstrated that higher MWL increased drivers’ RT in the majority of the participants. Furthermore, results also indicated a number of participants that probably employed adaptive control behaviors to counterbalance the increased MWL. Overall, variance on MWL proved to play an important role on driver performance, and thus further research on its consequences on driving performance, and the factors that influence its variance during driving, is imperative.
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Kumah, Kingsley K., Joost C. B. Hoedjes, Noam David, Ben H. P. Maathuis, H. Oliver Gao y Bob Z. Su. "Combining MWL and MSG SEVIRI Satellite Signals for Rainfall Detection and Estimation". Atmosphere 11, n.º 9 (19 de agosto de 2020): 884. http://dx.doi.org/10.3390/atmos11090884.
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Accurate rainfall detection and estimation are essential for many research and operational applications. Traditional rainfall detection and estimation techniques have achieved considerable success but with limitations. Thus, in this study, the relationships between the gauge (point measurement) and the microwave links (MWL) rainfall (line measurement), and the MWL to the satellite observations (area-wide measurement) are investigated for (area-wide) rainfall detection and rain rate retrieval. More precisely, we investigate if the combination of MWL with Meteosat Second Generation (MSG) satellite signals could improve rainfall detection and rainfall rate estimates. The investigated procedure includes an initial evaluation of the MWL rainfall estimates using gauge measurements, followed by a joint analysis of the rainfall estimates with the satellite signals by means of a conceptual model in which clouds with high cloud top optical thickness and large particle sizes have high rainfall probabilities and intensities. The analysis produced empirical thresholds that were used to test the capability of the MSG satellite data to detect rainfall on the MWL. The results from Kenya, during the “long rains” of 2013, 2014, and 2018 show convincing performance and reveal the potential of MWL and MSG data for area-wide rainfall detection.
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Aljamal, Yousef M. "FROM RADICALISM TO TOLERANCE: MEDIA COVERAGE OF THE MUSLIM WORLD LEAGUE". POLITICS AND RELIGION JOURNAL 16, n.º 1 (14 de julio de 2022): 95–110. http://dx.doi.org/10.54561/prj1601095a.
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Following its establishment in 1962, the Muslim World League (MWL) was meant to be an organization that expands the outreach of Saudi Arabia and its then Wahabi version of Islam in the world in the time when other competing ideologies, especially Arab nationalism, were on the rise. This allowed it to carry out religious, cultural, aid and educational programs. At the time, The Saudi adopted version of Islam known as Wahabism was rejected in the western world. This study analyses news reports about the MWL published by mostly western media outlets, by using Critical Discourse Analysis as a theory. This study concludes that the coverage of MWL has changed recently from being negative to being positive with Mohammad Al-Issa assuming the leadership of MWL and with radical changes taking place in Saudi Arabia itself, politically, socially, religiously and culturally. Western media coverage of MWL now connects the organization to coexistence, religious tolerance, openness and moderate thinking and positive view of other faiths. It suggests that MWL has rejected all forms of radicalism and strict interpretation of Islam and calls for unity and building bridges with other religions.
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Cordero, Christian John y Kevinilo Marquez. "Extraction of Milled Wood Lignin from Coffee Husk (Coffea Arabica L.) and the Analysis of Its Potential as a UV-Protective Component of Lotion and Sunscreen". KIMIKA 32, n.º 2 (2 de septiembre de 2021): 1–10. http://dx.doi.org/10.26534/kimika.v32i2.1-10.
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This study aims to determine the effect of adding milled wood lignin (MWL) to the sun protection factor (SPF) of commercially available lotion and sunscreen. The MWL was isolated from Coffea Arabica L. husks using the Björkman method. FT-IR spectroscopic analysis showed two characteristic peaks located at around 1200 cm-1 and 1300 cm-1, which indicates the presence of guaiacyl and syringyl groups. UV-Vis spectroscopic analysis showed two peaks located at around 278 nm and 325 nm, which indicates the presence of guaiacyl and some conjugated phenolic groups, respectively. The isolated MWL was then added to commercially available sunscreen and lotion at various concentrations. The sun protection factor (SPF) was then determined using the Mansur method and UV-Vis Spectroscopy. Results have shown that from 0% to 40 % by mass of MWL added, there was an observable average increase from 0.90 to 13.86 SPF for lotion, while there was an increase from 26.47 to 34.00 SPF for sunscreen. Results suggest that for lotion the SPF significantly increased if MWL was added from 0% up to 40% while for sunscreen the SPF significantly increased if MWL was added from 0% up to 20%.
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Pearson, Joseph y Helmut Cölfen. "Practical Aspects of Multiwavelength Analytical Ultracentrifugation". Instruments 3, n.º 1 (21 de marzo de 2019): 23. http://dx.doi.org/10.3390/instruments3010023.
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Open-source Multiwavelength Analytical Ultracentrifugation (MWL-AUC) detection systems have been evolving for over a decade. Continual advances emerging out of several research groups have brought the instrumentation technology to increasingly higher levels of performance. The capabilities of MWL-AUC have been documented in many publications, demonstrating the applicability of broad spectrum absorbance acquisitions in analytical ultracentrifugation to a wide array of scientific fields. Despite numerous examples of the usefulness and unique advantages of MWL-AUC, the adoption of the technology by more research groups has been slow. The complexity of the hardware, integration within an ultracentrifuge platform and lack of practical construction and operational information is the likely source of reluctance. Here, we clearly describe the challenges facing a researcher considering adopting MWL-AUC technology in their own laboratories, and provide the information necessary to implement and operate a MWL-AUC system. The discussion includes details of detector assembly, optical alignment, and acquisition parameter settings necessary to achieve high quality experimental results.
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Baoguo, Wu, Lui Shunxi, Fang Guizhen y Chen Zhenlong. "Structural analysis of Tetracetron sinense MWL". Journal of Northeast Forestry University 3, n.º 2 (noviembre de 1992): 84–94. http://dx.doi.org/10.1007/bf02843042.
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Yoshida, Masanori, Etsuro Shimizu, Masashi Sugomori y Ayako Umeda. "Identification of the Relationship between Maritime Autonomous Surface Ships and the Operator’s Mental Workload". Applied Sciences 11, n.º 5 (5 de marzo de 2021): 2331. http://dx.doi.org/10.3390/app11052331.
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Shipping is an indispensable tool for the sustainable global supply chain, and seafarers play a key role in safe navigation. Maritime autonomous surface ships (MASS) have been expected to reduce marine accidents by human error of the seafarers. On the other hand, MASS may have adverse effects on operators’ mental workload (MWL) and increase safety risks in some cases. This research aims to provide a scheme for identifying the relationship between MWL and MASS in the maritime that can be utilised for rulemaking and technological development. The provided scheme identifies the factors that affect the MWL of operators and sub-elements of MWL through gap analysis. Five factors related to MASS operation were defined, in addition to general factors. The case study was carried out by utilising the scheme on typical cases focusing on the normal navigational situation. The NASA task load index method was used to measure MWL. Ten deck officers with various ranks, including the third officer and captain, participated in the case study. The results suggested that various causes such as conflicted situations, machine–human interfaces, mechanical-style movements of the ship, reliability of MASS, and visibility constraints affect the MWL of operators. It also confirmed the verification of the identification scheme.
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Jalilian, Hamed, Zahra Zamanian, Omid Gorjizadeh, Shahrzad Riaei, Mohammad Reza Monazzam y Mohammad Abdoli-Eramaki. "Autonomic Nervous System Responses to Whole-Body Vibration and Mental Workload: A Pilot Study". International Journal of Occupational and Environmental Medicine 10, n.º 4 (1 de octubre de 2019): 174–84. http://dx.doi.org/10.15171/ijoem.2019.1688.
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Background: Whole-body vibration (WBV) and mental workload (MWL) are common stressors among drivers who attempt to control numerous variables while driving a car, bus, or train. Objective: To examine the individual and combined effects of the WBV and MWL on the autonomic nervous system. Methods: ECG of 24 healthy male students was recorded using NeXus-4 while performing two difficulty levels of a computerized dual task and when they were exposing to WBV (intensity 0.5 m/s2; frequency 3–20 Hz). Each condition was examined for 5 min individually and combined. Inter-beat intervals were extracted from ECG records. The time-domain and frequency-domain heart rate variability parameters were then extracted from the inter-beat intervals data. Results: A significant (p=0.008) increase was observed in the mean RR interval while the participants were exposed to WBV; there was a significant (p=0.02) reduction in the mean RR interval while the participants were performing the MWL. WBV (p=0.02) and MWL significantly (p<0.001) increased the standard deviation of normal-to-normal intervals with a moderate-to-large effect size. All active periods increased the low-frequency component and low-frequency/high-frequency ratio. However, only the WBV significantly increased the highfrequency component. A significant (p=0.01) interaction was observed between the WBV and MWL on low-frequency component and low-frequency/high-frequency ratio. Conclusion: Exposure to WBV and MWL can dysregulate the autonomic nervous system. WBV stimulates both sympathetic and parasympathetic nervous system; MWL largely affects sympathetic nervous system. Both variables imbalance the sympatho-vagal control as well.
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Zhang, Jianhua, Jianrong Li y Rubin Wang. "Instantaneous mental workload assessment using time–frequency analysis and semi-supervised learning". Cognitive Neurodynamics 14, n.º 5 (12 de mayo de 2020): 619–42. http://dx.doi.org/10.1007/s11571-020-09589-3.
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Abstract The real-time assessment of mental workload (MWL) is critical for development of intelligent human–machine cooperative systems in various safety–critical applications. Although data-driven machine learning (ML) approach has shown promise in MWL recognition, there is still difficulty in acquiring a sufficient number of labeled data to train the ML models. This paper proposes a semi-supervised extreme learning machine (SS-ELM) algorithm for MWL pattern classification requiring only a small number of labeled data. The measured data analysis results show that the proposed SS-ELM paradigm can effectively improve the accuracy and efficiency of MWL classification and thus provide a competitive ML approach to utilizing a large number of unlabeled data which are available in many real-world applications.
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Bläsing, Dominic y Manfred Bornewasser. "Influence of Increasing Task Complexity and Use of Informational Assistance Systems on Mental Workload". Brain Sciences 11, n.º 1 (14 de enero de 2021): 102. http://dx.doi.org/10.3390/brainsci11010102.
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(1) Background: Cognitive aspects and complexity in modern manual mixed model assembly are increasing. To reduce mental workload (MWL), informational assistance systems are introduced. The influence of complexity and used assistance system on MWL should be investigated to further improve the implementation of such assistance systems. (2) Methods: Using a simulated close to real-life assembly task a 2 × 3 design was chosen, with two levels of assembly complexity (within subjects) and three different assistance systems (paper, Augmented Reality (AR)-glasses, tablet–between subjects). MWL was measured using either physiological response (electrocardiogram (ECG) and eye-tracking) or performance indicators. (3) Results: An influence of task complexity on MWL can be shown. Additionally, usability based differences between the used assistance systems become more evident with reference to the results of area of interest analysis. (4) Conclusions: Using a multi-modal measurement approach, it is possible to detect complexity-based differences in MWL. Additional research on validity and alignment is needed to further use these for (neuro-) ergonomic considerations and recommendations.
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Vasquez, Holland M., Justin G. Hollands y Greg A. Jamieson. "The Effects of Practice on Navigation Performance and Mental Workload with a Mirror-In-The-Sky Map". Proceedings of the Human Factors and Ergonomics Society Annual Meeting 65, n.º 1 (septiembre de 2021): 1546–50. http://dx.doi.org/10.1177/1071181321651060.
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Some previous research using a new augmented reality map display called Mirror-in-the-Sky (MitS) showed that performance was worse and mental workload (MWL) greater with MitS relative to a track-up map for navigation and wayfinding tasks. The purpose of the current study was to determine—for both MitS and track-up map—how much performance improves and MWL decreases with practice in a simple navigation task. We conducted a three-session experiment in which twenty participants completed a route following task in a virtual environment. Task completion times and collisions decreased, subjective MWL decreased, and secondary task performance improved with practice. The NASA-TLX Global ratings and Detection Response Task Hit Rates showed a larger decrease in MWL with MitS than the track-up map. Additionally, means for performance and workload measures showed that differences between the MitS and track-up map decreased in the first session. In later sessions the differences between the MitS and track-up map were negligible. As such, with practice performance and MWL may be comparable to a traditional track-up map.
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GOYAL, ASHOK y SUKANTA DUTTA. "CONSTRAINING THE RIGHT-HANDED INTERACTIONS FROM PION CONDENSATE MATTER". International Journal of Modern Physics A 15, n.º 04 (10 de febrero de 2000): 509–22. http://dx.doi.org/10.1142/s0217751x00000240.
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We consider right-handed neutrino emission from charged and neutral pion condensate matter that could have been present in the supernova core associated with SN 1987 A. This is used to constrain the strength of right-handed interactions and we get an excluded range of values for the right-handed W boson and extra neutral Z' boson masses. For vanishing WL–WR mixing we obtain (1.3–1.8) MWL ≈≤ MWR ≤≈ (370–700) MWL and (1.3–1.8) MWL ≈≤ MN' ≤≈ 158MWL.
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Kumah, Kingsley K., Joost C. B. Hoedjes, Noam David, Ben H. P. Maathuis, H. Oliver Gao y Bob Z. Su. "The MSG Technique: Improving Commercial Microwave Link Rainfall Intensity by Using Rain Area Detection from Meteosat Second Generation". Remote Sensing 13, n.º 16 (19 de agosto de 2021): 3274. http://dx.doi.org/10.3390/rs13163274.
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Commercial microwave link (MWL) used by mobile telecom operators for data transmission can provide hydro-meteorologically valid rainfall estimates according to studies in the past decade. For the first time, this study investigated a new method, the MSG technique, that uses Meteosat Second Generation (MSG) satellite data to improve MWL rainfall estimates. The investigation, conducted during daytime, used MSG optical (VIS0.6) and near IR (NIR1.6) data to estimate rain areas along a 15 GHz, 9.88 km MWL for classifying the MWL signal into wet–dry periods and estimate the baseline level. Additionally, the MSG technique estimated a new parameter, wet path length, representing the length of the MWL that was wet during wet periods. Finally, MWL rainfall intensity estimates from this new MSG and conventional techniques were compared to rain gauge estimates. The results show that the MSG technique is robust and can estimate gauge comparable rainfall estimates. The evaluation scores every three hours of RMSD, relative bias, and r2 based on the entire evaluation period results of the MSG technique were 2.61 mm h−1, 0.47, and 0.81, compared to 2.09 mm h−1, 0.04, and 0.84 of the conventional technique, respectively. For convective rain events with high intensity spatially varying rainfall, the results show that the MSG technique may approximate the actual mean rainfall estimates better than the conventional technique.
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Pe III, Justin Alfred, Ji Sun Mun y Sung Phil Mun. "Thermal characterization of kraft lignin prepared from mixed hardwoods". BioResources 18, n.º 1 (6 de diciembre de 2022): 926–36. http://dx.doi.org/10.15376/biores.18.1.926-936.
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Thermal characterization of kraft lignin (KL) prepared from mixed hardwoods was conducted to determine their thermal and thermo-oxidative stability, glass transition temperature (Tg), pyrolysis products composition, and syringyl/guaiacyl ratio. Two milled wood lignins (MWLs) from acacia (MWL-aca) and mixed hardwoods (MWL-mhw), the same hardwood species employed in the production of KL, were also characterized for comparison with KL. Thermogravimetric analysis (TGA) indicated that KL had higher thermal and thermo-oxidative stability than MWLs. Based on differential scanning calorimetry (DSC), the Tg of KL was 63.2 °C, while MWLs gave similar values near 165 °C. The syringyl (S), guaiacyl (G), p-hydroxyphenyl (H) composition of KL acquired from pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) at 675 °C was 48:44:8 (S/G ratio 1.07), while MWL-aca and MWL-mhw were 31:60:9 and 46:48:6, respectively.
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Zhao, Yunbo, Junyi Zhou, Hujun Niu y Yimin Xie. "Elucidation of bioactivity of tricin released by thioacidolysis from wheat straw lignin". BioResources 18, n.º 4 (31 de agosto de 2023): 7295–308. http://dx.doi.org/10.15376/biores.18.4.7295-7308.
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Tricin is a complex compound with chemical bonds to phenylpropane units of lignin in gramineous plants, and it is predominantly bound to lignin by β-O-4 ether bonds. Thioacidolysis cleaves the alkyl aryl ether bonds, which releases tricin from the tricin-lignin complex and maintains the natural structure of the tricin. In this study, milled wood lignin (MWL) was isolated from wheat straw by Bjӧrkman’s method, and the MWL was subjected to thioacidolysis to release tricin from the MWL. Medium-pressure preparative liquid chromatography was used for further purification. FT-IR and 1H-NMR analyses showed that the purified fraction was composed mainly of tricin-type flavonoids. The extracted tricin had strong scavenging capacity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals, with a half maximal inhibitory concentration (IC50) of 51.9 mg/L. Drug sensitivity paper testing showed that the extracted tricin inhibited the growth of Escherichia coli. The bacteriostatic circle diameters of tricin from wheat straw MWL and quercetin standard were 9.17 and 7.52 mm, respectively. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that the tricin from wheat straw MWL had possible inhibitory effect on lung cancer A549 cells, with a maximum inhibitory performance of 44.5%.
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HR, Mokhtarinia. "Common Subjective Mental Workload Assessment Measures: Advantages and Disadvantages". Ergonomics International Journal 8, n.º 1 (23 de enero de 2024): 1–4. http://dx.doi.org/10.23880/eoij-16000317.
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Background: The amount of mental resources required to perform simultaneously a series tasks is considered as mental workload (MWL). High and Low mental workload in the workplace is usually associated with mental fatigue, decreased performance, human error, and even harmful long-term health effects. Among the various MWL assessment techniques, the outcome measures such as questionnaires are easier and more practical in workplace settings. We aimed to compare the three current commonly advocated and used questionnaires. Material and Methods: Three common different outcome measures for evaluation of the MWL are NASA Task Load Index (NASA-TLX), Subjective Workload Assessment Technique (SWAT), and the CarMen-Q workload questionnaire. Among them the NASA-TLX is well known and more popular with six subscales that are used extensively in industrial and official workplaces. SWAT is the simplest one with three dimensions. The NASA-TLX is preferable method because of its higher sensitivity, especially in low MWL conditions. The CarMen-Q questionnaire is a new questionnaire with 29 items and 4 subscales that focuses on cognitive workload and mental fatigue. Conclusion: SWAT is the simplest and less sensitive measure than the NASA-TLX and CarMen-Q questionnaires. In contrast, the NASA-TLX is widely used and more known instrument for MWL evaluation.
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Tokuda, Satoru, Evan Palmer, Edgar Merkle y Alex Chaparro. "Using Saccadic Intrusions to Quantify Mental Workload". Proceedings of the Human Factors and Ergonomics Society Annual Meeting 53, n.º 12 (octubre de 2009): 809–13. http://dx.doi.org/10.1177/154193120905301210.
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This study proposes a new method to quantify mental workload (MWL) automatically, without interfering with the operator's primary task performance. An unobtrusive Tobii eye tracker recorded eye movements while participants were engaged in a cognitively demanding N-back task. Original algorithms automatically analyzed the eye data, detected specific eye deviation movements called saccadic intrusions (SIs), and automatically quantified the eye deviation accounted for SIs. This SI measure was strongly correlated with the task difficulty levels in the N-back tasks and with pupil diameter. This indicates that the SI measure appeared to reflect MWL and may be used as a measure of MWL.
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Yang, Qiulin, Dan Huo, Jianbin Shi, Lu Lin, Qiujuan Liu, Qingxi Hou, Hongjie Zhang y Chuanling Si. "Structural properties of the purified lignins of cornstalk in the cooking process with a solid alkali". BioResources 10, n.º 4 (18 de septiembre de 2015): 7489–500. http://dx.doi.org/10.15376/biores.10.4.7489-7500.
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The process of cooking with solid alkali is a novel and efficient technology. In the present work, milled wood lignin (MWL) and water-soluble milled wood lignin (WMWL) were used as the raw materials to research their properties when cooking with MgO and active oxygen. Before and after cooking, the lignin content of the samples was estimated using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), heteronuclear single-quantum coherence-nuclear magnetic resonance (HSQC-NMR), and gel permeation chromatography (GPC). The results showed that the properties of the MWL and WMWL were different. The G unit and A′structure in WMWL were more easily degraded than that in the MWL, where the G unit could be oxidized into a novel G′ unit. The D structure in the MWL with a weak signal could be thoroughly degraded, and the P structure was only present in WMWL and could be generated during the cooking process.
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Mastropietro, Alfonso, Ileana Pirovano, Alessio Marciano, Simone Porcelli y Giovanna Rizzo. "Reliability of Mental Workload Index Assessed by EEG with Different Electrode Configurations and Signal Pre-Processing Pipelines". Sensors 23, n.º 3 (26 de enero de 2023): 1367. http://dx.doi.org/10.3390/s23031367.
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Background and Objective: Mental workload (MWL) is a relevant construct involved in all cognitively demanding activities, and its assessment is an important goal in many research fields. This paper aims at evaluating the reproducibility and sensitivity of MWL assessment from EEG signals considering the effects of different electrode configurations and pre-processing pipelines (PPPs). Methods: Thirteen young healthy adults were enrolled and were asked to perform 45 min of Simon’s task to elicit a cognitive demand. EEG data were collected using a 32-channel system with different electrode configurations (fronto-parietal; Fz and Pz; Cz) and analyzed using different PPPs, from the simplest bandpass filtering to the combination of filtering, Artifact Subspace Reconstruction (ASR) and Independent Component Analysis (ICA). The reproducibility of MWL indexes estimation and the sensitivity of their changes were assessed using Intraclass Correlation Coefficient and statistical analysis. Results: MWL assessed with different PPPs showed reliability ranging from good to very good in most of the electrode configurations (average consistency > 0.87 and average absolute agreement > 0.92). Larger fronto-parietal electrode configurations, albeit being more affected by the choice of PPPs, provide better sensitivity in the detection of MWL changes if compared to a single-electrode configuration (18 vs. 10 statistically significant differences detected, respectively). Conclusions: The most complex PPPs have been proven to ensure good reliability (>0.90) and sensitivity in all experimental conditions. In conclusion, we propose to use at least a two-electrode configuration (Fz and Pz) and complex PPPs including at least the ICA algorithm (even better including ASR) to mitigate artifacts and obtain reliable and sensitive MWL assessment during cognitive tasks.
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Lange, Werner y Oskar Faix. "Lignin-Polyphenol Interaction in Azobe (Lophira alata) Heartwood. A Study on Milled Wood Lignin (MWL) and Klason Residues". Holzforschung 53, n.º 5 (10 de septiembre de 1999): 519–24. http://dx.doi.org/10.1515/hf.1999.085.
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Summary Findings about anomalous high Klason residues of azobe (Lophira alata) heartwood prompted a search for methods of determination of non lignin-type polyphenols in lignin preparations. A four step procedure was performed: (1) ethylation of milled wood lignins (MWLs) from azobe and beech heartwood, (2) permanganate oxidation, (3) methylation, and (4) GC analysis of the oxidation products. Besides the well known degradation products of hemipinic, iso-hemipinic, and meta-hemipinic acid type, methyl-3,4-diethoxy-benzoate (compound I) has also been detected among the oxidation products. The oxidation of beech MWL gave rise only to 0.4 mol % of I but azobe MWL yielded the remarkably high amount of 10.7 mol % of I. As lignins do not contain two adjacent aromatic hydroxyl groups, we concluded that I is of polyflavonoid origin. Hence the extraordinarily high Klason residues of azobe heartwood can be rationalized with large amounts of acid insoluble polyphenols which are an integral part of the azobe cell wall and which is also closely associated to MWLs. Ethylation followed by KMnO4 oxidation is an effective tool to detect polyflavonoids in lignins.
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Liu, Chenglin, Chenyang Zhang, Luohao Sun, Kun Liu, Haiyue Liu, Wenbing Zhu y Chaozhe Jiang. "Detection of Pilot’s Mental Workload Using a Wireless EEG Headset in Airfield Traffic Pattern Tasks". Entropy 25, n.º 7 (10 de julio de 2023): 1035. http://dx.doi.org/10.3390/e25071035.
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Elevated mental workload (MWL) experienced by pilots can result in increased reaction times or incorrect actions, potentially compromising flight safety. This study aims to develop a functional system to assist administrators in identifying and detecting pilots’ real-time MWL and evaluate its effectiveness using designed airfield traffic pattern tasks within a realistic flight simulator. The perceived MWL in various situations was assessed and labeled using NASA Task Load Index (NASA-TLX) scores. Physiological features were then extracted using a fast Fourier transformation with 2-s sliding time windows. Feature selection was conducted by comparing the results of the Kruskal-Wallis (K-W) test and Sequential Forward Floating Selection (SFFS). The results proved that the optimal input was all PSD features. Moreover, the study analyzed the effects of electroencephalography (EEG) features from distinct brain regions and PSD changes across different MWL levels to further assess the proposed system’s performance. A 10-fold cross-validation was performed on six classifiers, and the optimal accuracy of 87.57% was attained using a multi-class K-Nearest Neighbor (KNN) classifier for classifying different MWL levels. The findings indicate that the wireless headset-based system is reliable and feasible. Consequently, numerous wireless EEG device-based systems can be developed for application in diverse real-driving scenarios. Additionally, the current system contributes to future research on actual flight conditions.
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Ghalib, Hussein B. "The local meteoric relationship for 18O and 2H in precipitations and isotopic compositions of water resources in northeast Amara area (South of Iraq)". International Journal of Hydrology 4, n.º 4 (31 de agosto de 2020): 176–80. http://dx.doi.org/10.15406/ijh.2020.04.00243.
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This paper focuses on determining the Amara meteoric water line for the study area (AMWL) is defined or the first time, based on samples of precipitation collected Amara city - southeast of Iraq. For an adequate management of available water resources in semi-arid and arid regions, it is important to compare isotopic data of surface water and groundwater with the local meteoric relationship for d18O and dD in precipitations.Isotope values of precipitation indicate a local meteoric water line (Amara MWL δ2H = 7.51 δ18O + 10.82; R2=0.94) situated between the Mediterranean MWL and Global MWL. Both the slope and 2H intercept for AMWL are deviated from the global meteoric water line - GMWL (δ2H = 8.13 18O + 10) and Mediterranean MWL (δ 2H = 8.13 18O + 22). The slightly variation in isotopic compositions of the Missan rain (from -4 to +3.2‰ and from -20 to -14‰ for 18O and 2H, respectively) is because of slightly seasonal changes in precipitations in this area. The 18O and 2H isotopes of local water resources show that the rainwater is affected by the Arabian Gulf Arabian Sea potential moisture sources.
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Fasching, Mario, Philipp Schröder, R. Petra Wollboldt, Hedda K. Weber y Herbert Sixta. "A new and facile method for isolation of lignin from wood based on complete wood dissolution". Holzforschung 62, n.º 1 (1 de enero de 2008): 15–23. http://dx.doi.org/10.1515/hf.2008.003.
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Abstract A new method for the isolation of lignin in high yield from wood and pretreated wood is presented, avoiding the liquid-solid extraction step of the classical milled wood lignin (MWL) isolation. Dissolved wood lignin (DWL) was obtained by total dissolution of ball milled wood in dimethylsulfoxide and N-methylimidazole (DMSO/NMI) followed by precipitation in dioxane/water in the course of which lignin and carbohydrate fractions were separated. The lignin fraction was purified. High lignin yields and the low number of separation steps belong to the advantages of the described method. DWL lignin was isolated from beech wood (Fagus sylvatica L.) and the sample was compared to MWL obtained by the classical Björkman method. Elemental analyses, methoxyl group content, potassium permanganate oxidation, infrared spectroscopy, and 1D and 2D nuclear magnetic resonance spectroscopy indicated that both lignin preparations are quite similar. However, MWL contained significantly more phenolic hydroxyl groups than DWL. The results indicated that MWL contains higher amounts of smaller fractions with broken β-O-4 linkages than DWL.
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Yang, Jing, Iris Charlene Layadi, Juan P. Wachs y Denny Yu. "Adaptive Human-Robotic Interaction for Robotic-assisted Surgical Settings". Military Medicine 188, Supplement_6 (1 de noviembre de 2023): 480–87. http://dx.doi.org/10.1093/milmed/usad210.
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ABSTRACT Introduction Increased complexity in robotic-assisted surgical system interfaces introduces problems with human–robot collaboration that result in excessive mental workload (MWL), adversely impacting a surgeon’s task performance and increasing error probability. Real-time monitoring of the operator’s MWL will aid in identifying when and how interventions can be best provided to moderate MWL. In this study, an MWL-based adaptive automation system is constructed and evaluated for its effectiveness during robotic-assisted surgery. Materials and Methods This study recruited 10 participants first to perform surgical tasks under different cognitive workload levels. Physiological signals were obtained and employed to build a real-time system for cognitive workload monitoring. To evaluate the effectiveness of the proposed system, 15 participants were recruited to perform the surgical task with and without the proposed system. The participants’ task performance and perceived workload were collected and compared. Results The proposed neural network model achieved an accuracy of 77.9% in cognitive workload classification. In addition, better task performance and lower perceived workload were observed when participants completed the experimental task under the task condition supplemented with adaptive aiding using the proposed system. Conclusions The proposed MWL monitoring system successfully diminished the perceived workload of participants and increased their task performance under high-stress conditions via interventions by a semi-autonomous suction tool. The preliminary results from the comparative study show the potential impact of automated adaptive aiding systems in enhancing surgical task performance via cognitive workload-triggered interventions in robotic-assisted surgery.
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Kim, Jin-Sook, Dukhwan Lim, Ha-Na Hong, Hyun-Wook Shin, Ki-Do Lee, Bin-Na Hong y Jung-Hak Lee. "Development of Korean Standard Monosyllabic Word Lists for School Aged Children(KS-MWL-S) and Preschoolers(KS-MWL-P)". Audiology and Speech Research 4, n.º 2 (31 de diciembre de 2008): 141–60. http://dx.doi.org/10.21848/audiol.2008.4.2.141.
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Van Acker, Bram B., Peter Conradie, Peter Vlerick y Jelle Saldien. "Employee Acceptability of Wearable Mental Workload Monitoring in Industry 4.0: A Pilot Study on Motivational and Contextual Framing". Proceedings of the Design Society: International Conference on Engineering Design 1, n.º 1 (julio de 2019): 2101–10. http://dx.doi.org/10.1017/dsi.2019.216.
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AbstractAs Industry 4.0 will greatly challenge employee mental workload (MWL), research on objective wearable MWL-monitoring is in high demand. However, numerous research lines validating such technology might become redundant when employees eventually object to its implementation. In a pilot study, we manipulated two ways in which employees might perceive MWL-monitoring initiatives. We found that framing the technology in terms of serving intrinsic goals (e.g., improving health) together with an autonomy-supportive context (e.g., allowing discussion) yields higher user acceptability when compared to framing in terms of extrinsic goals (e.g., increasing productivity) together with a controlling context (e.g., mandating use). User acceptability still panned out neutral in case of the former, however - feeding into our own and suggested future work.
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önnerud, H., M. Palmblad y G. Gellerstedt. "Investigation of Lignin Oligomers Using Electrospray Ionisation Mass Spectrometry". Holzforschung 57, n.º 1 (8 de enero de 2003): 37–43. http://dx.doi.org/10.1515/hf.2003.006.
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Summary Electrospray ionisation Fourier transform ion cyclotron resonance mass spectrometry (MS) and size exclusion chromatography (SEC) was utilised for analysis of milled wood lignin (MWL) and lignin model compounds degraded by thioacidolysis. MS and SEC showed that thioacidolysis was an efficient method for degradation of the β-O-4 bond in lignin. Moreover, the molecular weight of thioacidolysed pinoresinol and MWL were analysed using matrix assisted laser desorption ionisation time-of-flight mass spectrometry. Tandem MS was successfully applied for the structural determination of thioacidolysed pinoresinol with and without acetylation of the product. The MS results of thioacidolysis on MWL resulted in the identification of a tetrameric lignin structure containing a 5-O-4, 5-5, β-1 linkage pattern.
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Zinovyev, Grigory, Ivan Sumerskii, Thomas Rosenau, Mikhail Balakshin y Antje Potthast. "Ball Milling’s Effect on Pine Milled Wood Lignin’s Structure and Molar Mass". Molecules 23, n.º 9 (1 de septiembre de 2018): 2223. http://dx.doi.org/10.3390/molecules23092223.
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The effect of ball milling expressed as the yield of milled wood lignin (MWL) on the structure and molar mass of crude milled wood lignin (MWLc) preparation is studied to better understand the process’ fundamentals and find optimal conditions for MWL isolation (i.e., to obtain the most representative sample with minimal degradation). Softwood (loblolly pine) MWLc preparations with yields of 20–75% have been isolated and characterized based on their molar mass distribution (by Size Exclusion Chromatography (SEC)), hydroxyl groups of different types (31P NMR), methoxyl groups (HS-ID GC-MS), and sugar composition (based on methanolysis). Classical MWL purification is not used to access the whole extracted lignin. The results indicate that lignin degradation during ball milling occurs predominantly in the high molar mass fraction and is less pronounced in the low molar mass fraction. This results in a significant decrease in the Mz and Mw of the extracted MWLc with an increase in the yield of MWLc, but has only a very subtle effect on the lignin structure if the yield of MWLc is kept below about 55%. Therefore, no tedious optimization of process variables is necessary to achieve the required MWLc yield in this range for structural studies of softwood MWL. The sugar composition shows higher amounts of pectin components in MWLs of low yields and higher amounts of glucan and mannan in high-yield MWLs, confirming that lignin extraction starts from the middle lamella in the earlier stages of MWL isolation, followed by lignin extraction from the secondary wall region.
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Mohamed, Tarek Mahrous Korany, Jianmin Gao, Mohamed E. Abuarab, Mohamed Kassem, Essam Wasef y Wessam El-Ssawy. "Applying Different Magnetic Water Densities as Irrigation for Aeroponically and Hydroponically Grown Strawberries". Agriculture 12, n.º 6 (7 de junio de 2022): 819. http://dx.doi.org/10.3390/agriculture12060819.
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Due to the scarcity of water, it is necessary to develop an environmentally friendly method for increasing water productivity and crop production. An experiment was conducted to assess the effects of different magnetic levels (magnetic water level 1 (MWL 1) = 3800 Gauss, magnetic water level 2 (MWL 2) = 5250 Gauss, and magnetic water level 3 (MWL 3) = 6300 Gauss, as well as normal water (NW) as a control) in combination with three soilless culture systems (a nutrient film technique (NFT) hydroponics system, a tower aeroponics system, and a pyramidal aeroponics system. The results showed that the utilization of magnetic water had significant effects on the yield and growth of strawberry plants The tower aeroponic system under MWL 3 produced the highest yield and water productivity, with increases of 80.9% and 89%, respectively, over the control. The tower aeroponic system under MWL 3 produced the highest yield and water productivity, with increases of 80.9% and 89%, respectively, over the control. In addition, as compared to the NW, the NFT system increased yield and water productivity by 71.1% and 79.3%, respectively, whilst the pyramidal system increased yield and water productivity by 66.87% and 82%, respectively. Furthermore, when compared to the control, the combination of the NFT system and magnetic water level 3 (MWL 3) resulted in the most leaves, largest stem diameter, and largest leaf area of the strawberry plants resulted in the most leaves, stem diameter, and leaf area of strawberry plants. In comparison to all other treatments, this combination produced the best fruit quality and yield, as well as its constituents, such as titratable acidity, total soluble solids, and fruit hardness. This study found that combining magnetic therapy with soilless culture techniques resulted in increased yield and water productivity. In addition, water and fertigation solution usage in the NFT, tower, and pyramidal systems dropped by 4.8%, 6%, and 4.8%, respectively. Furthermore, it enhanced plant morphology and plant quality.
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ALVES CARVALHO, JANAÍNA, MAYARA DE SOUZA MIRANDA, MATHEUS FELIPE FREIRE PEGO, ELTON FRANCISQUINI, DIEIMES RIBEIRO RESENDE y MARIA LUCIA BIANCHI. "SUGARCANE BAGASSE LIGNIN OBTAINED BY DIFFERENT EXTRACTION METHODS". Cellulose Chemistry and Technology 55, n.º 1-2 (12 de febrero de 2021): 55–62. http://dx.doi.org/10.35812/cellulosechemtechnol.2021.55.06.
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Sugarcane bagasse (SB) is a by-product of ethanol production obtained in large quantities worldwide, including Brazil. Lignin is one of SB components, and its extraction is of great interest due to its vast potential for use. In this study, sugarcane bagasse was subjected to two methods of lignin extraction to obtain: Klason lignin (LKL) and milled wood lignin (MWL). The syringil/guaiacyl ratio of the lignin obtained from sugarcane bagasse was 1.67. Thermogravimetric analysis showed that LKL is more resistant to thermal degradation than MWL. According to the FTIR spectra, LKL yields a more oxidized lignin, presenting greater changes in its structure than MWL. Thus, this study provides information on the changes caused by different extractions and strengthens future studies on the transformation of lignin into products of high added value.
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Hu, Zhoujian, Ting-Feng Yeh, Hou-min Chang, Yuji Matsumoto y John F. Kadla. "Elucidation of the structure of cellulolytic enzyme lignin". Holzforschung 60, n.º 4 (1 de julio de 2006): 389–97. http://dx.doi.org/10.1515/hf.2006.061.
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Abstract Cellulolytic enzyme lignin (CEL) and milled wood lignin (MWL) were prepared by three different ball-milling methods. The structure of CEL at various yields was elucidated and compared with MWL using wet chemical analysis, FTIR and solution-state NMR techniques. Results show that ball milling of wood degrades β-O-4 structures in lignin. However, even after extensive ball milling, less than 25% of the β-O-4 structures were degraded. The extent of degradation was less for softwood than for hardwood lignin. Extractable lignin yield, either MWL or CEL, was the best way to assess the extent and effect of ball milling. CEL is preferred over MWL, as it can be isolated in higher yield with less degradation. CEL was isolated at yields ranging from 20% to 86%. Over this range the CEL had similar structures, suggesting that lignin in the secondary wall is uniform in structure. The residual enzyme lignin (REL) was structurally different from CEL and may originate mainly from the middle lamella. In this paper we propose a new procedure for the isolation of lignin for use in structural studies, whereby wood is sufficiently milled and successively extracted to produce three lignin fractions representing the total lignin in wood.
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Sik Kim, Yong, Hou‐min Chang y John F. Kadla. "Polyoxometalate (POM) Oxidation of Milled Wood Lignin (MWL)". Journal of Wood Chemistry and Technology 27, n.º 3-4 (1 de noviembre de 2007): 225–41. http://dx.doi.org/10.1080/02773810701702188.
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Ridha, Ali A. "Indoor risk assessment of radon gas in the science college buildings-University of Mustansiriyah using RAD-7 detector". Iraqi Journal of Physics (IJP) 13, n.º 27 (4 de febrero de 2019): 97–101. http://dx.doi.org/10.30723/ijp.v13i27.268.
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In the present work, a set of indoor Radon concentration measurements was carried out in a number of rooms and buildings of Science College in the University of Mustansiriyah for the first time in Iraq using RAD-7 detector which is an active method for short time measuring compared with the passive method in solid state nuclear track detectors (SSNTD's). The results show that, the Radon concentrations values vary from 9.85±1.7 Bq.m-3 to 94.21±34.7 Bq.m-3 with an average value 53.64±26 Bq.m-3 which is lower than the recommended action level 200-300 Bq/m3 [ICRP, 2009].The values of the annual effective dose (A.E.D) vary from 0.25 mSv/y to 2.38 mSv/y, with an average value 1.46±0.67 mSv/y which is lower than the recommended the range 3-10 mSv/y [ICRP, 1993]. While the values of lung cancer cases per year per million person vary from 4.50 per million person to 42.84 per million person with an average value 24.35±12 per million person which is lower than the recommended range 170-230 per million person [ICRP, 1993].The values of the potential alpha energy concentration were found to vary from 10.18 mWL to 1.06 mWL, with an average value 5.79±2.8 mWL which is lower than the recommended value of 53.33 mWL given by [UNSCEAR, 1993].
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Mehta, Vimal, Deep Shikha, Pal Singh, Pal Chauhan y Singh Mudahar. "Measurment of radon, thoron and their progeny in indoor environment of Mohali, Punjab, Northern India, using pinhole dosimeters". Nuclear Technology and Radiation Protection 31, n.º 3 (2016): 299–305. http://dx.doi.org/10.2298/ntrp1603299m.
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The health hazards of radon and its decay products above certain levels are well known. However, for any preventive measures to be taken, we have to be aware of radon levels of that particular area. Measurement of radon and its decay products in indoor environments is an important aspect of assessing indoor air quality and health conditions associated with it. Keeping this in mind, measurements of radon, thoron and their progeny concentrations were carried out in Mohali, Northern India, using pinhole-based twin cup dosimeters. Radon exhalation rates of soil samples in the dwellings/areas were measured via an active technique of a continuous radon monitor. The indoor radon concentration in Mohali varied from 15.03 ? 0.61 Bq/m3 to 39.21 ? 1.46 Bq/m3 with an average of 26.95 Bq/m3 ,while thoron concentration in the same dwellings varied from 9.62 ? 0.54 Bq/m3 to 52.84 ? 2.77 Bq/m3 with an average of 31.09 Bq/m3. Radon progeny levels in dwellings under study varied from 1.63 to 4.24 mWL, with an average of 2.94 mWL, while thoron progeny levels varied from 0.26 to 1.43 mWL , with an average of 0.84 mWL. The annual dose received by the inhabitants of dwellings under study varied from 0.78 to 2.36 mSv, with an average of 1.61 mSv. The in situ gamma dose rate varied from 0.12 to 0.32 mSv/h.
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Fencl, M., J. Rieckermann, M. Schleiss, D. Stránský y V. Bareš. "Assessing the potential of using telecommunication microwave links in urban drainage modelling". Water Science and Technology 68, n.º 8 (1 de octubre de 2013): 1810–18. http://dx.doi.org/10.2166/wst.2013.429.
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The ability to predict the runoff response of an urban catchment to rainfall is crucial for managing drainage systems effectively and controlling discharges from urban areas. In this paper we assess the potential of commercial microwave links (MWL) to capture the spatio-temporal rainfall dynamics and thus improve urban rainfall-runoff modelling. Specifically, we perform numerical experiments with virtual rainfall fields and compare the results of MWL rainfall reconstructions to those of rain gauge (RG) observations. In a case study, we are able to show that MWL networks in urban areas are sufficiently dense to provide good information on spatio-temporal rainfall variability and can thus considerably improve pipe flow prediction, even in small subcatchments. In addition, the better spatial coverage also improves the control of discharges from urban areas. This is especially beneficial for heavy rainfall, which usually has a high spatial variability that cannot be accurately captured by RG point measurements.
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Al-Hamidawi, Ali Abid Abojassim. "Monitoring of220Rn Concentrations in Buildings of Kufa Technical Institute, Iraq". Science and Technology of Nuclear Installations 2015 (2015): 1–5. http://dx.doi.org/10.1155/2015/738019.
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This paper presents the measurements of thoron and the progeny in fifteen buildings in Kufa Technical Institute, Iraq, from June 2015 to April 2015 using RAD-7 detectors. Also, annual effective dose rate was calculated in all buildings under study. The thoron concentration varies from05.35±0.58 Bq/m3to53.50±1.82 Bq/m3with an average18.39±4.18 Bq/m3. The concentration of thoron daughters was found to vary from 0.14 mWL to 1.44 mWL with an average0.53±0.11 mWL. The annual effective doses due to thoron mainly vary from 0.042 mSv/y to 0.81 mSv/y with an average0.20±0.06 mSv/y. The preliminary results in this study indicate that they may be suitable for evaluating the indoor220Rn and its progeny concentrations whenever the public exposure to220Rn and its progeny is taken into account. During this survey, the continuous difficulty in measuring thoron was also pointed out, due to its short half-life and faults in the measuring system.
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Carrasco, Mikael y Merritt L. Drewery. "91 Mealworm and black soldier fly larvae as protein supplements for beef steers consuming forage". Journal of Animal Science 102, Supplement_1 (1 de marzo de 2024): 14–15. http://dx.doi.org/10.1093/jas/skae019.016.
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Abstract The global population is projected to increase, indicating there will be greater demand for animal protein to meet the associated food needs. This demand will place additional pressure on livestock systems to increase output while also minimizing natural resource inputs. Insect protein has emerged as a potential environmentally sustainable alternative to conventional protein feeds, such as soybean meal. Further, insect protein does not compete in the human food market as the products of conventional oil crops often do. Mealworm larvae (MWL) has been studied in poultry and swine as an alternative protein feed; however, there is not currently research evaluating MWL for cattle. Black soldier fly larvae (BSFL) has also received attention for its potential use in livestock feed due to its scalability and nutritional value, but research in cattle is limited. The objective of this study was to evaluate the effects of whole dried MWL and defatted BSFL as protein supplements for cattle consuming forage. These procedures were approved by IACUC at Texas State University (#7726). Five ruminally cannulated steers were utilized in a 5×5 Latin square experiment to determine how MWL and BSFL supplementation affect forage utilization. Steers consuming low-quality forage (4.2% crude protein) were provided one of five treatments each period: 1) control with no supplement (CON), 2) soybean meal (CONV), 3) BSFL, 4) MWL, and a 5) 50% BSFL and 50% MWL by-weight (MIX). Supplements were provided at 100 mg N/kg BW. Periods included 8-d for treatment adaptation, 5-d for intake and digestion measurements, and 1-d for ruminal fermentation measures. Dry matter (DM), organic matter (OM), CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) were determined for diet, ort, and feces. Protein supplementation stimulated forage OM intake (P ≤ 0.01) relative to CON. There was a significant difference in FOMI (P ≤ 0.01) between BSFL and CONV. Steers receiving CONV treatment consumed 4.71 kg FOMI/d, which was significantly greater (P ≤ 0.01) than those receiving BSFL (4.30 kg/d). There were not differences in FOMI between other treatment groups. Total digestible OM intake (TDOMI) was stimulated by protein supplementation (P ≤ 0.01) from 1.94 kg/d for CON to an average of 3.24 kg/d across protein supplements. Organic matter digestibility (OMD) and neutral detergent fiber digestibility (NDFD) were not affected by treatment (P ≥ 0.37), for an average OMD of 66.5% and NDFD of 62.7%. There was also not a treatment effect (P = 0.96) on total volatile fatty acid (VFA) concentrations, although there were some shifts in molar proportions of individual VFAs across treatments. These data indicate that MWL may be more efficacious than BSFL in stimulating forage utilization in beef cattle, but both are viable protein supplements.
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Mahgoub, Mohamed Ali, Ahmed Mahmoud Zeina, Ahmed Mohamed Bahaa El-Din, Ahmed Hassan El-Sabbagh, Franco Bassetto y Vincenzo Vindigni. "Gluteal Region Reshaping of Massive Weight Loss Patients—A Decision-Making Strategy". Archives of Plastic Surgery 49, n.º 03 (mayo de 2022): 289–95. http://dx.doi.org/10.1055/s-0042-1748640.
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Abstract Background Massive weight loss (MWL) is a very common presentation that you may face as a plastic surgeon. Each patient has his own individual criteria, so, you should work according to a well-organized plan, especially when such cases have concerns about their gluteal area contour that were neglected before by many surgeons. A decision-making strategy was used to give a personalized treatment for targeting gluteal region reshaping of MWL patients. Methods This study considered all patients with MWL subjected to buttock reshaping. There was no randomization in treatment; there was a case-by-case assessment. We analyzed the features of the buttocks, the type of surgery performed, the outcomes, and the complications. Results Fifty two patients were included (41 females and 11 males), ages ranged between 21 and 66 years. Demographic data, preoperative body mass index (BMI), duration of surgery, type of surgery, and postoperative complications were collected. Statistically significant improvements were observed in gluteal ptosis and patient satisfaction grades. Conclusion Aesthetic improvement of the buttocks involves either augmentation or contouring that may be obtained by liposculpture, surgical lifting, or combination. Patients with MWL have high expectations and are often treated with multiple procedures. Thus, an easy strategic approach personalized on each patient to treat multiple adjacent areas in one operation is necessary. Adipose tissue distribution, gluteal skin status, and BMI were the main factors that can forcefully affect our plan to guarantee reduction of unpleasant results and complications and improve patient satisfaction.
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Zhang, Congfei, Lihong Zhao, Weiying Li, Junli Ren, Hongyuan Wang y Beihai He. "The Limitation of Unproductive Binding of Cellulases to Lignin by Ozone Pretreatment". Applied Sciences 14, n.º 6 (9 de marzo de 2024): 2318. http://dx.doi.org/10.3390/app14062318.
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The limitation of enzymatic saccharification of lignocellulose is attributed to the nonproductive adsorption between lignin and cellulase. This study aims to investigate the effects of ozone pretreatment on the physical structure and chemical properties of milled wood lignin (MWL). The objective is to reduce the non-productive adsorption of cellulase on lignin. The structure–activity relationship between the physical structure of MWL and the occurrence of nonproductive adsorption was analysed using two-dimensional heteronuclear single quantum coherence–nuclear magnetic resonance (HSQC-NMR) and phosphorus-31 nuclear magnetic resonance spectrum (31P-NMR), etc. The results indicate that ozone pretreatment resulted in a decrease in the phenolic hydroxyl content and S/G ratio, an increase in the carboxyl content, and a negative zeta potential of MWL. The maximum adsorption capacity decreased from 25.77 mg/g to 10.09 mg/g, the Langmuir constant decreased from 13.86 mL/mg to 10.11 mL/mg, and the binding strength decreased from 357.14 mL/g to 102.04 mL/g, as determined by Langmuir isothermal adsorption. This suggests that ozone pretreatment resulted in a reduction in the hydrophobicity of lignin and a weakening of the electrostatic attraction between lignin and cellulase, thereby effectively reducing the non-productive adsorption of cellulase on lignin. This study provides an environmentally friendly pretreatment technique and comprehensively analyses the structural changes of ozone-treated MWL. These findings contribute to a deeper understanding of the interaction between lignin and cellulase.
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Wu, Jun, Shaowei Fan, Minghe Jin y Hong Liu. "OPTIMIZATION OF MODIFIED WATT’S LINKAGE FOR AN APPROXIMATELY LONG STRAIGHT PATH WITHIN LIMITED DIMENSION". Transactions of the Canadian Society for Mechanical Engineering 40, n.º 3 (septiembre de 2016): 399–417. http://dx.doi.org/10.1139/tcsme-2016-0029.
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This paper presents an optimal method of aiming for an approximately straight path of the Modified Watt’s Linkage (MWL) within limited dimension. A modification to the Watt’s linkage and the corresponding condition are introduced, followed by the kinematic synthesis. The path generation based on the modification considering constraints from practical application is provided. Genetic algorithm is utilized to perform the constrained optimization. The centrosymmetric property of the MWL is considered in the synthesis process. Ideal parameters of the mechanism are achieved to demonstrate the effectiveness of the proposed method.
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González, Josefa Becerra. "VHE BL Lacs through the MAGIC glasses". Proceedings of the International Astronomical Union 10, S313 (septiembre de 2014): 64–69. http://dx.doi.org/10.1017/s174392131500188x.
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AbstractIn this contribution an overview of the latest results on the study of BL Lac objects with the MAGIC telescopes at the very high energy (VHE, E>100 GeV) gamma-rays is presented. Three new VHE sources were detected during 2014, two BL Lac objects and the gravitational lensed blazar S3 0218+357. MAGIC detected very fast intra-night variability from IC 310. This detection points to smaller emitting regions than the event horizon, this is hard to be explained in the framework of the current theoretical models. The long term multi wavelength (MWL) study of the BL Lac PKS 1424+240 shows correlation between the radio and optical emission, pointing to a common origin. The MWL SED is not well fitted by a one-zone synchrotron-self Compton (SSC) model, but a two-zone SSC model can explain both, the MWL light curve and the SED. Spectral curvature has been found in the observed VHE spectrum from PG 1553+113. This is the first time that spectral curvature compatible with the EBL absorption is found in an individual object.
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Planke, Lars J., Yixiang Lim, Alessandro Gardi, Roberto Sabatini, Trevor Kistan y Neta Ezer. "A Cyber-Physical-Human System for One-to-Many UAS Operations: Cognitive Load Analysis". Sensors 20, n.º 19 (23 de septiembre de 2020): 5467. http://dx.doi.org/10.3390/s20195467.
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The continuing development of avionics for Unmanned Aircraft Systems (UASs) is introducing higher levels of intelligence and autonomy both in the flight vehicle and in the ground mission control, allowing new promising operational concepts to emerge. One-to-Many (OTM) UAS operations is one such concept and its implementation will require significant advances in several areas, particularly in the field of Human–Machine Interfaces and Interactions (HMI2). Measuring cognitive load during OTM operations, in particular Mental Workload (MWL), is desirable as it can relieve some of the negative effects of increased automation by providing the ability to dynamically optimize avionics HMI2 to achieve an optimal sharing of tasks between the autonomous flight vehicles and the human operator. The novel Cognitive Human Machine System (CHMS) proposed in this paper is a Cyber-Physical Human (CPH) system that exploits the recent technological developments of affordable physiological sensors. This system focuses on physiological sensing and Artificial Intelligence (AI) techniques that can support a dynamic adaptation of the HMI2 in response to the operators’ cognitive state (including MWL), external/environmental conditions and mission success criteria. However, significant research gaps still exist, one of which relates to a universally valid method for determining MWL that can be applied to UAS operational scenarios. As such, in this paper we present results from a study on measuring MWL on five participants in an OTM UAS wildfire detection scenario, using Electroencephalogram (EEG) and eye tracking measurements. These physiological data are compared with a subjective measure and a task index collected from mission-specific data, which serves as an objective task performance measure. The results show statistically significant differences for all measures including the subjective, performance and physiological measures performed on the various mission phases. Additionally, a good correlation is found between the two physiological measurements and the task index. Fusing the physiological data and correlating with the task index gave the highest correlation coefficient (CC = 0.726 ± 0.14) across all participants. This demonstrates how fusing different physiological measurements can provide a more accurate representation of the operators’ MWL, whilst also allowing for increased integrity and reliability of the system.
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Balakshin, Mikhail, Ewellyn Augsten Capanema, Xuhai Zhu, Irina Sulaeva, Antje Potthast, Thomas Rosenau y Orlando J. Rojas. "Spruce milled wood lignin: linear, branched or cross-linked?" Green Chemistry 22, n.º 13 (2020): 3985–4001. http://dx.doi.org/10.1039/d0gc00926a.
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Ando, Daisuke, Fumiaki Nakatsubo, Toshiyuki Takano, Hiroshi Nishimura, Masato Katahira y Hiroyuki Yano. "Multi-step degradation method for β-O-4 linkages in lignins: γ-TTSA method. Part 3. Degradation of milled wood lignin (MWL) from Eucalyptus globulus". Holzforschung 67, n.º 8 (1 de diciembre de 2013): 835–41. http://dx.doi.org/10.1515/hf-2013-0008.
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Abstract Milled wood lignin (MWL) of Eucalyptus globulus has been treated by a selective degradation method for β-O-4 linkages, which lets the lignin carbohydrate complexes (LCC) intact. The method consists of four reaction steps: (1) γ-tosylation, (2) thioetherification, (3) sulfonylation and (4) mild alkali treatment (γ-TTSA method). Each step was followed by spectroscopies for chemical structural analysis; especially, the HSQC-NMR analysis was in focus. It was demonstrated that β-O-4 linkages were selectively and quantitatively cleaved by the γ-TTSA method while the β-β linkages in the MWL remained intact. The method leads to an enrichment of LCCs.
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Gadi, S. K., A. Osorio -Cordero, Rogelio Lozano y R. Garrido. "Human Adaptation Towards a Force Augmenting Device: Experimental Results". Journal of Applied Science & Process Engineering 4, n.º 2 (3 de octubre de 2017): 205–12. http://dx.doi.org/10.33736/jaspe.437.2017.
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This short communication article presents an experiment to test the existence of mental workload (MWL) and adaptability of a human operator (HO) in handling force augmenting devices (FADs). An experiment is conducted where the HOs of three different ages are allowed to handle a FAD with high augmentation factor. Augmentation factor gives the factor by which the HO’s force is amplified. It is observed that the HOs were unable to stabilize the FAD for the first time. With the help of these experiments, it is observed that a human adapts itself to achieve a stable HA-FAD interaction. In another perspective, it can be observed that HO undergoes MWL to handle a FAD with high augmentation factor.