bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydration Is More Important Than Exogenous Carbohydrate Intake During Push-to-the-Finish Cycle Exercise in the Heat
Authors: Berry Craig W. , Wolf S. Tony , Cottle Rachel M. , Kenney W. Larry
Published: October 2021

Dehydration ≥2% loss of body mass is associated with reductions in performance capacity, and carbohydrate (CHO)-electrolyte solutions (CES) are often recommended to prevent dehydration and provide a source of exogenous carbohydrate during exercise. It is also well established that performance capacity in the heat is diminished compared to cooler conditions, a response attributable to greater cardiovascular strain caused by high skin and core temperatures. Because hydration status, environmental conditions, and carbohydrate availability interact to influence performance capacity, we sought to determine how these factors affect push-to-the-finish cycling performance. Ten young trained cyclists exercised at a moderate intensity (2.5 W·kg−1) in a hot-dry condition [40°C, 20% relative humidity (RH)] until dehydration of ~2% body mass. Subjects then consumed either no fluid (NF) or enough fluid (water, WAT; Gatorade®, GAT; or GoodSport™, GS) to replace 75% of lost body mass over 30 min. After a 30-min light-intensity warm-up (1.5 W·kg−1) in a 35°C, 20% RH environment, subjects then completed a 120-kJ time trial (TT). TT time-to-completion, absolute power, and relative power were significantly improved in WAT (535 ± 214 s, 259 ± 99 W, 3.3 ± 0.9 W·kg−1), GAT (539 ± 226 s, 260 ± 110 W, 3.3 ± 1.0 W·kg−1), and GS (534 ± 238 s, 262 ± 105 W, 3.4 ± 1.0 W·kg−1) compared to NF (631 ± 310 s, 229 ± 96 W, 3.0 ± 0.9 W·kg−1) all (p < 0.01) with no differences between WAT, GAT, and GS, suggesting that hydration is more important than carbohydrate availability during exercise in the heat. A subset of four subjects returned to the laboratory to repeat the WAT, GAT, and GS treatments to determine if between-beverage differences in time-trial performance were evident with a longer TT in thermoneutral conditions. Following dehydration, the ambient conditions in the environmental chamber were reduced to 21°C and 20% RH and subjects completed a 250-kJ TT. All four subjects improved TT performance in the GS trial (919 ± 353 s, 300 ± 100 W, 3.61 ± 0.86 W·kg−1) compared to WAT (960 ± 376 s, 283 ± 91 W, 3.43 ± 0.83 W·kg−1), while three subjects improved TT performance in the GAT trial (946 ± 365 s, 293 ± 103 W, 3.60 ± 0.97 W·kg−1) compared to WAT, highlighting the importance of carbohydrate availability in cooler conditions as the length of a push-to-the-finish cycling task increases.
Novel Approach to Assess Cardiac Function Using Systolic Performance and Myocardial Performance Indices From Simultaneous Electrocardiography and Phonocardiography Recordings in Dogs With Various Stages of Myxomatous Mitral Valve Disease
Authors: Gicana Karlo Romano B. , Lertwanakarn Tuchakorn , Tachampa Kittipong
Published: October 2021

Background and Objective:Myxomatous mitral valve disease (MMVD) progression entails changes in the structural and functional properties of the heart affecting cardiac timings and intervals within the cardiac cycle. Conventionally, echocardiography is used to determine the cardiac time intervals (CTIs) including systolic and myocardial performance indices (SPI and MPI) in evaluating cardiac function. Alternatively, these CTIs can also be measured using simultaneous recordings of electrocardiography (ECG) and phonocardiography (PCG), but their values in different MMVD stages remain to be established. This study aimed to establish and prove the use of derived SPI and MPI from a dedicated device as a novel approach to assess cardiac function in different stages of MMVD dogs.

Materials and Methods:A prospective study in 52 dogs with different MMVD stages measured the CTIs using a novel device. These were compared and correlated with standard echocardiographic parameters. The predictive value of SPI and three new proposed formulas to estimate MPI (i.e., F1, F2, and F3) in association with asymptomatic from symptomatic MMVD dogs were investigated.

Results:Our findings revealed that CTI parameters measured from a novel device including QS1, QS2, S1S2, MPI-F1, and MPI-F2 were altered at different stages of MMVD. The SPI and all proposed MPI formulas were comparable with the systolic time interval and Tei index from echocardiography. In addition, the SPI, MPI-F1, and MPI-F2 were significantly correlated with the Tei index. However, the SPI was not able to differentiate the various stages of MMVD. Conversely, only the MPI-F1 (i.e., (QS1 + S2)/S1S2) demonstrated good predictive accuracy when compared between asymptomatic and symptomatic MMVD dogs similar to the Tei index. Moreover, this formula was able to differentiate stages B1 and C with remarkable predictive accuracy, higher sensitivity, and high specificity when compared with the Tei index.

Conclusion:We have successfully described the CTI parameters in different MMVD stages using simultaneous ECG and PCG recordings in dogs. Furthermore, we have proven that the concept of using the newly proposed parameters from a novel device is equivalent to the Tei index. Thus, we established a novel approach to evaluate cardiac function and its supportive use in the diagnosis of MMVD patients.
Multi-Objective UAV Positioning Mechanism for Sustainable Wireless Connectivity in Environments with Forbidden Flying Zones
Authors: Atli İbrahim , Ozturk Metin , Valastro Gianluca C. , Asghar Muhammad Zeeshan
Published: October 2021

A communication system based on unmanned aerial vehicles (UAVs) is a viable alternative for meeting the coverage and capacity needs of future wireless networks. However, because of the limitations of UAV-enabled communications in terms of coverage, energy consumption, and flying laws, the number of studies focused on the sustainability element of UAV-assisted networking in the literature was limited thus far. We present a solution to this problem in this study; specifically, we design a Q-learning-based UAV placement strategy for long-term wireless connectivity while taking into account major constraints such as altitude regulations, nonflight zones, and transmit power. The goal is to determine the best location for the UAV base station (BS) while reducing energy consumption and increasing the number of users covered. Furthermore, a weighting method is devised, allowing energy usage and the number of users served to be prioritized based on network/battery circumstances. The suggested Q-learning-based solution is contrasted to the standard k-means clustering method, in which the UAV BS is positioned at the centroid location with the shortest cumulative distance between it and the users. The results demonstrate that the proposed solution outperforms the baseline k-means clustering-based method in terms of the number of users covered while achieving the desired minimization of the energy consumption.
Robust Control Design Based on Perturbation Cancellation for Micro-Positioning Design with Hysteresis
Authors: Chen Yung-Yue , Lan Yu-Jen , Zhang Yi-Qing
Published: October 2021

Based on the superiority of the piezoelectric elements, including lightweight, high electric mechanical transformation efficiency and a quick response time, a piezoelectric-based micro-positioning actuator is developed in this investigation. For eliminating the effects of hysteresis and modeling uncertainties that appeared in this micro-positioning actuator, a nonlinear adaptive fuzzy robust control design with a perturbation cancellation ability is proposed for this micro-positioning design to achieve a positioning resolution of 1 μm. Structurally, this proposed robust control methodology contains two particular parts: a universal fuzzy approximator and a robust compensator, which are employed to cancel the modeling uncertainties caused by the perturbed parts of the micro-positioning actuator and mitigate the approximation error between the modeling uncertainties and the universal fuzzy approximator, respectively. From both the numerical simulations and real validations, this proposed micro-positioning design performs a promising positioning performance in the micrometer level.
Hysteresis Modeling of a PAM System Using ANFIS
Authors: Abu Mohareb Saad , Alsharkawi Adham , Zgoul Moudar
Published: October 2021

Pneumatic artificial muscles (PAMs) are excellent environmentally friendly actuators and springs that remain somewhat underutilized in the industry due to their hysteretic behavior, which makes predicting their behavior difficult. This paper presents a novel black-box approach that employs an adaptive-network-based fuzzy inference system (ANFIS) to create pressure-contraction hysteresis models. The resulting models are simulated in a control system toolbox to test their controllability using a simple proportional-integral (PI) controller. The data showed that the models created based on fixed inputs had an average normalized root mean square error (RMSE) of 0.0327, and their generalized counterparts achieved an average normalized RMSE of 0.04087. The simulation results showed that the PI controller was able to achieve mean tracking errors of 8.1 µm and 18.3 µm when attempting to track a sinusoidal and step references, respectively. This work concludes that modeling using the ANFIS is limited to being able to know the derivative of the input pressure or its rate of change, but competently models hysteresis in PAMs across multiple operating ranges. This is the highlight of this work. Additionally, these ANFIS-created models lend themselves well to controller, but exploring more refined control schemes is necessary to fully utilize them.
Role of Rhizosphere Soil Microbes in Adapting Ramie (Boehmeria nivea L.) Plants to Poor Soil Conditions through N-Fixing and P-Solubilization
Authors: Wu Shenglan , Jie Hongdong , Jie Yucheng
Published: October 2021

The N-fixing and P-solubilization functions of soil microbes play a vital role in plant adaptation to nutrient-deficiency conditions. However, their exact roles toward the adaptation of ramie to poor soil conditions are still not clear. To fill this research gap, the N-fixing and P-solubilization efficiencies of soils derived from the rhizosphere of several ramie genotypes with different levels of poor soil tolerance were compared. Correlations between the N-fixing, P-solubilization efficiency, and the poor soil tolerable index were analyzed to quantify their contributions towards the adaptation of ramie plants to poor soil conditions. To explore how the microorganisms affected the potential of N-fixing/P-solubilization, the activities of the nutrients related the soil enzymes were also tested and compared. The results of this study confirm the existence of N-fixing and P-solubilization bacteria in the ramie rhizosphere of the soil. The number of N-fixing bacteria varied from 3010.00 to 46,150.00 c.f.u. per gram dry soil for the ramie treatment, while it was only 110.00 c.f.u. per gram dry soil for treatment without ramie cultivation. The average P-solubilization efficiency of ramie treatment was almost five times higher than that of the control soil (0.65 vs. 0.13 mg mL−1). The significant correlations between the poor soil tolerance index and the N-fixing bacteria number (r = 0.829)/nitrogenase activity (r = 0.899) suggest the significantly positive role of N-fixing function in the adaptation of ramie plants to poor soil. This is also true for P-solubilization, as indicated by the significant positively correlation coefficients between the ramie poor soil tolerance index and P-solubilization efficiency (0.919)/acid phosphatase activity (0.846). These characteristics would accelerate the application of “holobiont” breeding for improving ramie nutrient use efficiency.
Changes in Proximate Chemical and Mineral Compositions of Different Sex Categories of Mutton during the Dry-Curing Process
Authors: Krvavica Marina , Đugum Jelena , Topalović Marijana Drinovac , Kegalj Andrijana , Ljubičić Iva , Konjačić Miljenko
Published: October 2021

The aim of this research was to determine the effect of sex, castration, and processing on the chemical properties of mutton in the production of kaštradina—a traditional Dalmatian dry-cured meat product. Therefore, the carcasses of 20 ewes (E), 20 rams (R), and 20 wethers (W) of the Dalmatian pramenka breed were processed by dry-curing. On the 1st, 35th, and 60th days of processing, the samples from the scapulae were taken, then the proximate chemical, NaCl, and mineral analyses were performed, and significant differences between most of the parameters were found. Unlike W, the R samples contained significantly more proteins (p < 0.01), NaCl (p < 0.05), and potassium (p < 0.05) and less fat (p < 0.05). Furthermore, compared to the W and R categories, the E category of kaštradina contained significantly more calcium (p < 0.05). The higher contents of intramuscular fat, potassium, and calcium and lower content of NaCl could positively affect the sensory (marbling, flavor, juiciness, and tenderness) and chemical (fatty acid profile) properties of kaštradina. These findings suggest that the W and E raw mutton could be a better-quality raw material for production of kaštradina than could the R, but further research is needed for a more comprehensive picture of its quality.
Supplementation of Mixed Organic Acids Improves Growth Performance, Meat Quality, Gut Morphology and Volatile Fatty Acids of Broiler Chicken
Authors: Ma Jiayu , Wang Jian , Mahfuz Shad , Long Shenfei , Wu Di , Gao Jie , Piao Xiangshu
Published: October 2021

Background: Organic acid as a green feed additive is increasingly favoured by enterprises and scholars, but little emphasis has been placed on the effect of organic acids on broiler meat quality. Methods: A total of 192 male chicks (one-day-old, weighted 48.40 ± 0.64 g) were selected to investigate the effect of mixed organic acids (MOA) on growth performance, meat quality as well as fatty acids profile. Chicks were randomly allocated to three treatments with eight replicates and eight chicks per replicate, including a corn–soybean basal diet with 0 (CON), 3000 mg/kg (low MOA; LMOA), and 6000 mg/kg (high MOA; HMOA) MOA. The experiment was divided into starter (d 1–d 21) and grower (d 22–d 42) phases. Results: Broilers supplemented with LMOA and HMOA enhanced (p < 0.05) the final body weight and average daily gain in the grower and overall phases. An improved (p < 0.05) feed conversion ratio in the grower and overall phases was observed in broilers supplemented with LMOA. The breast and thigh muscles pH24h were higher (p < 0.05) in broilers fed with HMOA and the redness in thigh meat was also improved (p < 0.05). Additionally, supplementing LMOA increased (p < 0.05) the saturated fatty acids, unsaturated fatty acids and the ratio of polyunsaturated fatty acids to saturated fatty acids in breast meat. A positive effect occurred (p < 0.05) on jejunal villus height and ileal crypt depth in 21 d broilers supplemented with HMOA. Conclusion: Our findings indicated that dietary supplementation of MOA could improve the growth performance, meat quality, and fatty acids profile, as well as intestinal morphology. Furthermore, diets supplemented with mixed organic acids at 3000 mg/kg may be more desirable, considering the overall experimental results in broilers.
Visual Signaling in the Semi-Fossorial Lizard Pholidobolus montium (Gymnophthalmidae)
Authors: Poma-Soto Franco , Narváez Andrea E. , Romero-Carvajal Andrés
Published: October 2021

It has been suggested that gymnophthalmids, like most semi-fossorial lacertoids, rely more in chemical cues to communicate, in comparison to other groups, like Iguanids, on which communication is mostly based on visual signaling. We present the first description of visual signaling in the Andean lizard Pholidobolusmontium (Gymnophthalmidae) and a complete ethogram based on ex situ observations (34 different types of behaviors including positions and simple movements). Through the design of conspecific stimulus experiments, we were able to recognize leg-waving as a visual signal, as it is only displayed in presence of conspecifics or in presence of a mirror and was one of first and most frequent displays in this context. We also detected other visual displays like neck-arching and tail-undulation which may also be relevant as visual signals. Based on our results, we propose that visual signaling is also possible in semi-fossorial lizards; however, further studies regarding chemical signal recognition and color detection are required to confirm our hypothesis.
Use of Chemical Nano-Selenium as an Antibacterial and Antifungal Agent in Quail Diets and Its Effect on Growth, Carcasses, Antioxidant, Immunity and Caecal Microbes
Authors: Alagawany Mahmoud , Qattan Shaza Y. A. , Attia Youssef A. , El-Saadony Mohamed T. , Elnesr Shaaban S. , Mahmoud Mohamed A. , Madkour Mahmoud , Abd El-Hack Mohamed E. , Reda Fayiz M.
Published: October 2021

Nano-minerals are used to enhance mineral bioavailability, which helps improve animal growth and health. The use of chemical nano-selenium (Che-SeNPs) has lately attracted great scientific interest, mainly due to its potential benefits for poultry. The current study was conducted to investigate the impact of the dietary supplementation of Che-SeNPs on the growth performance, carcass traits, blood constituents, antioxidant status, immunity, and gut microbiota of Japanese quails. A total of one week-old 180 Japanese quails were randomly distributed into four equal groups, and each group consisted of 45 unsexed birds with five replications (nine birds each). The first group was fed a basal diet without supplementation (0 g/kg Che-SeNPs), and the second, third, and fourth groups were fed diets containing 0.2, 0.4, and 0.6 g/kg Che-SeNPs, respectively. The results showed that the dietary supplementation of Che-SeNPs significantly (p < 0.0001) increased body weight, body weight gain, and feed conversion ratio, but decreased feed intake (p < 0.0001) compared to the control group. The highest values of growth performance were recorded in the group fed 0.4 g Che-SeNPs g/kg feed. Che-SeNPs levels did not affect the carcass traits, relative organs (except liver), or blood hematology (except platelet count and hemoglobin level) of quails. Plasma total protein, albumin, aspartate amino transferase (AST), and urea values were not affected by dietary Che-SeNPs, but alanine aminotransferase and lactate dehydrogenase values declined. Globulin and creatinine values were linearly increased with the inclusion of Che-SeNPs (0.4 and 0.6 g/kg) in quail diets compared to the control. The supplementation of Che-SeNPs in quail diets significantly improved (p < 0.05) the plasma lipid profile and activities of antioxidant enzymes compared to the control group. Immunoglobulin G values of Che-SeNPs (0.4 and 0.6 g/kg) were higher (p < 0.05) than those in the control group. The groups fed diets supplemented with Che-SeNPs showed lower (p < 0.0001) total bacterial count, total yeast and molds count, Coliform, Escherichia coli, Enterococcus spp., and Salmonella spp. colonization, and higher (p = 0.0003 and 0.0048) lactic acid bacteria counts than those in the control group. In conclusion, Che-SeNPs supplemented up to 0.4 g/kg can improve the performance, lipid profile, antioxidant indices, and immunity, as well as decrease intestinal pathogens in quails during the fattening period (1–5 weeks of age).
Scrapie at Abattoir: Monitoring, Control, and Differential Diagnosis of Wasting Conditions during Meat Inspection
Authors: Esteves Alexandra , Vieira-Pinto Madalena , Quintas Hélder , Orge Leonor , Gama Adelina , Alves Anabela , Seixas Fernanda , Pires Isabel , Pinto Maria de Lurdes , Mendonça Ana Paula , Lima Carla , Machado Carla Neves , Silva João Carlos , Tavares Paula , Silva Filipe , Bastos Estela , Pereira Jorge , Gonçalves-Anjo Nuno , Carvalho Paulo , Sargo Roberto , Matos Ana , Figueira Luís , Pires Maria dos Anjos
Published: October 2021

Wasting disease in small ruminants is frequently detected at slaughterhouses. The wasting disorder is manifested by the deterioration of the nutritional and physiological state of the animal indicated by thinness, emaciation, and cachexia. Evidence of emaciation and cachexia, alone, are pathological conditions leading to carcass condemnation during an inspection. Several diseases are associated with a wasting condition, including scrapie, pseudotuberculosis, tuberculosis, paratuberculosis, Maedi Visna, and tumor diseases. On the other hand, parasitic diseases, nutrition disorders, exposure or ingestion of toxins, metabolic conditions, inadequate nutrition due to poor teeth, or poor alimentary diet are conditions contributing to poor body condition. Classical and atypical scrapie is naturally occurring transmissible spongiform encephalopathies in small ruminants. The etiological agent for each one is prions. However, each of these scrapie types is epidemiologically, pathologically, and biochemically different. Though atypical scrapie occurs at low incidence, it is consistently prevalent in the small ruminant population. Hence, it is advisable to include differential diagnosis of this disease, from other possibilities, as a cause of wasting conditions detected during meat inspection at the abattoir. This manuscript is a review of the measures in force at the abattoir for scrapie control, focusing on the differential diagnosis of gross lesions related to wasting conditions detected in small ruminants during meat inspection.
Effects of Inositol Supplementation in Sperm Extender on the Quality of Cryopreserved Mesopotamian Catfish (Silurus triostegus, H. 1843) Sperm
Authors: Doğu Zafer , Şahinöz Erdinç , Aral Faruk , Koyuncu İsmail , Yüksekdağ Özgür
Published: October 2021

In this study, the effects of supplemented inositol on sperm extenders were examined on the spermatozoa motility rate and duration, total antioxidant and oxidant status, apoptotic spermatozoa and DNA damage, during the sperm post-thaw process of Mesopotamian Catfish (Silurus triostegus, H. 1843). The semen was frozen in diluents containing different inositol concentrations (5, 10, 20 and 40 mg). Increasing levels of inositol linearly improved the spermatozoa motility rate and duration significantly (p < 0.05). MDA and TOS were linearly decreased, however, TAS and GSH linearly increased (p < 0.05). The increasing inositol levels resulted in a linear and quadratic decrease in DNA damage in the comet assay, 8-hydroxydeoxyguanosine and the determined percentage of apoptotic spermatozoa (p < 0.05). These results suggest that there are many positive effects of the use of supplemental inositol on enhancing sperm cryopreservation efficiency in Silurus triostegus.
Effective Antimicrobial Solutions for Eradicating Multi-Resistant and β-Lactamase-Producing Nosocomial Gram-Negative Pathogens
Authors: Meade Elaine , Savage Micheal , Garvey Mary
Published: October 2021

Antimicrobial resistance (AMR) remains one of the greatest public health-perturbing crises of the 21st century, where species have evolved a myriad of defence strategies to resist conventional therapy. The production of extended-spectrum β-lactamase (ESBL), AmpC and carbapenemases in Gram-negative bacteria (GNB) is one such mechanism that currently poses a significant threat to the continuity of first-line and last-line β-lactam agents, where multi-drug-resistant GNB currently warrant a pandemic on their own merit. The World Health Organisation (WHO) has long recognised the need for an improved and coordinated global effort to contain these pathogens, where two factors in particular, international travel and exposure to antimicrobials, play an important role in the emergence and dissemination of antibiotic-resistant genes. Studies described herein assess the resistance patterns of isolated nosocomial pathogens, where levels of resistance were detected using recognised in vitro methods. Additionally, studies conducted extensively investigated alternative biocide (namely peracetic acid, triameen and benzalkonium chloride) and therapeutic options (specifically 1,10-phenanthroline-5,6-dione), where the levels of induced endotoxin from E. coli were also studied for the latter. Antibiotic susceptibility testing revealed there was a significant association between multi-drug resistance and ESBL production, where the WHO critical-priority pathogens, namely E. coli, K. pneumoniae, A. baumannii and P. aeruginosa, exhibited among the greatest levels of multi-drug resistance. Novel compound 1,10-phenanthroline-5,6-dione (phendione) shows promising antimicrobial activity, with MICs determined for all bacterial species, where levels of induced endotoxin varied depending on the concentration used. Tested biocide agents show potential to act as intermediate-level disinfectants in hospital settings, where all tested clinical isolates were susceptible to treatment.
An Easy-to-Use Procedure for the Measurement of Total Phenolic Compounds in Olive Fruit
Authors: Luaces Pilar , Pascual Mar , Pérez Ana G. , Sanz Carlos
Published: October 2021

Virgin olive oil (VOO) is one of the most emblematic products of the Mediterranean diet. Its content in phenolic compounds is strongly associated with the antioxidant and health-promoting properties of this diet. VOO’s phenolic profile is determined mainly by the phenolic compounds present in the olive fruit, so knowing their content allows for a fairly precise estimate of the antioxidant and functional properties of the corresponding oil. In this sense, a convenient, green, and sensitive spectrophotometric method was developed for the quantitative determination of total phenolic compounds in olive fruits. The method is based on an easy-to-use extraction procedure of olive fruit phenolics using dimethyl sulfoxide and quantification with the Folin–Ciocalteu reagent. Oleuropein proved to be a suitable reference compound for quantification, displaying a good linear response (r = 0.9996) over the concentration range of 0.58–6.48 mg/mL, with a variation coefficient of 0.42% and limits of detection and quantification of 0.0492 and 0.1490 mg/mL, respectively. The method was validated using a wide array of fruit samples representative of the Olea europaea L. genetic diversity. The results obtained with this spectrophotometric method, expressed as mg/mL of oleuropein, showed a good correlation with those obtained with the fruit samples analyzed by high performance liquid chromatography, with an r value of 0.9930 and a slope value of 1.022, confirming its reliability. Thus, this method can become a very useful simple tool to estimate the total phenolic content of olive fruits, especially when working with numerous samples such as in olive breeding programs or in commercial olive production, in which it is especially useful to know the phenolic state of the fruit and thus determine the optimal harvest date or the most appropriate agronomic treatment to increase the functional properties of the olive fruit and the olive oil.
Control of a Digital Galvanometer Scanner Using a Discrete-Time Sliding-Mode Variable-Structure Controller Based on a Decoupled Disturbance Compensator
Authors: Chen Guangsheng , Wang Yunlong
Published: October 2021

Laser processing plays an important role in industrial manufacturing, in which a galvanometer scanner (GS) functions as the core component of the laser processing equipment. With the development of the digital system, the GS based on the digital system finds a broader range of potential application. In order to address the slow step-responses of a GS with disturbance and parameter perturbation, the mathematical model of the motor of the GS is derived and a discrete-time sliding-mode variable-structure controller (DSVC) based on a decoupled disturbance compensator (DDC) (DSVC+DDC) is designed. The step-response performance of a GS is the key factor affecting the quality evaluation of laser processing. Experiments are conducted on the step responses of the motor of the GS on a digital experimental platform. The experiment results show that when guaranteeing a steady-state error within 20 urad and an overshoot of less than 5%, the rise time for step-responses in 1% and 10% of the whole stroke is 1 and 2 ms, decreasing by 23% and 58% compared with the reference performance index, which indicates the effectiveness of the proposed method. The proposed approach can not only compensate for the external disturbance online and improve the step-response speed of the GS, but also relax the traditionally assumed limit of the upper bound of external disturbance to the limit of the change rate of external disturbance, which reduces the difficulty of a practical application. This method has great significance for further applications in high precision machining.
Analysis of the Mechanism and Performance Optimization of Burying Weeding with a Self-Propelled Inter Row Weeder for Paddy Field Environments
Authors: Tang Han , Xu Changsu , Wang Qi , Zhou Wenqi , Wang Jinfeng , Xu Yanan , Wang Jinwu
Published: October 2021

To solve the problems of poor quality mechanical weeding and no obvious plowing effect in complex paddy field environments, the burying weeding operation mode was proposed. The height and force acting on the weeds were the main factors that altered the effectiveness of burying. The structure of the rake teeth weeding wheel was designed and matched with appropriate power, and the rake teeth weeding device was optimized. To verify the rationality of the designed device, the forward speed of the machine, rotating speed of the weeding wheels and weeding depth were selected as the experimental factors, and the inter row weeding rate was selected as the experimental index. A quadratic orthogonal rotation combination experiment with three factors and five levels was designed and optimized. The results showed that when the forward speed was 0.64 m/s, the rotational speed of the weeding wheel was 140 r/min, the weeding depth was 56.8 mm, the inter row weeding rate predicted by the model was 88.43%, and the inter row weeding rate was determined by a confirmatory experiment to be 87.06%, which met the weeding requirements for modern agronomy. To intuitively analyze how the soil was disturbed by the weeding wheel, the explicit dynamic analysis software LS-DYNA was used to build a fluid–solid coupling simulation model of the weeding wheel and water soil. The soil density and coupling stress were used to analyze the plowing state of paddy soil when the weeding wheel was operated. This study provides references for the design and development of paddy field weeding components and for mechanical and soil coupling simulation in paddy fields.
Recent Technical Progression in Photoacoustic Imaging—Towards Using Contrast Agents and Multimodal Techniques
Authors: Zhao Zuomin , Myllylä Teemu
Published: October 2021

For combining optical and ultrasonic imaging methodologies, photoacoustic imaging (PAI) is the most important and successful hybrid technique, which has greatly contributed to biomedical research and applications. Its theoretical background is based on the photoacoustic effect, whereby a modulated or pulsed light is emitted into tissue, which selectively absorbs the optical energy of the light at optical wavelengths. This energy produces a fast thermal expansion in the illuminated tissue, generating pressure waves (or photoacoustic waves) that can be detected by ultrasonic transducers. Research has shown that optical absorption spectroscopy offers high optical sensitivity and contrast for ingredient determination, for example, while ultrasound has demonstrated good spatial resolution in biomedical imaging. Photoacoustic imaging combines these advantages, i.e., high contrast through optical absorption and high spatial resolution due to the low scattering of ultrasound in tissue. In this review, we focus on advances made in PAI in the last five years and present categories and key devices used in PAI techniques. In particular, we highlight the continuously increasing imaging depth achieved by PAI, particularly when using exogenous reagents. Finally, we discuss the potential of combining PAI with other imaging techniques.
Intelligent Active Correction Technology and Application of Tower Displacement in Arch Bridge Cable Lifting Construction
Authors: Deng Nianchun , Yu Mengsheng , Yao Xinyu
Published: October 2021

In order to control the tower deviation in the cable hoisting process of long-span concrete-filled steel tubular arch bridge during construction monitoring, a practical method of tower deviation correction was studied and established. In the paper, based on the studies about the deviation error formation mechanism of tower in the process of cable lifting, the relevant formulas of the arch rib elevation changes caused by the change of tower state were deduced. The traditional control methods including increase of tower stiffness and strength of the anchor cable, are not effective, costly, and require a longer construction period. To overcome these defects, in virtue of the Beidou GNSS measurement system and hydraulic jack active control system, the active control technology of the CFST (Concrete Filled Steel Tube) arch bridge tower deviation was thoroughly studied. Besides, a perfect active control theory was established. Finally, the author puts forward the idea of reverse pulling tower deviation. The field measurement and comparative study show that after the optimization of this method, the tower deviation is within 2 cm, and the error meets the specification requirements. The proposed method can accurately control the tower deviation in the process of arch bridge cable hoisting, and establish a set of perfect active control related systems and theories, which is especially suitable for the construction monitoring and adjustment in the construction stage of arch bridge, and can provide reference for the construction control of tower deviation of the same type of bridge.
Mesh Size Selectivity of Tie-Down Gillnets for the Blackfin Flounder (Glyptocephalus stelleri) in Korea
Authors: Kim Pyungkwan , Kim Hyungseok , Kim Seonghun
Published: October 2021

Although gillnet fisheries are increasingly common in Korea, few studies have conducted sea trials using tie-down gillnets. Here, we analyzed the mesh size selectivity using tie-down gillnets with four different mesh sizes (84, 90, 105, and 120 mm) to catch blackfin flounders. A total of 10 sea trials were conducted at depths of 100–140 m in the waters of Yangyang County, Gangwon Province, Korea, and the catching efficiency and mesh size selectivity were comparatively analyzed. The net with a mesh size of 84 mm showed the highest number of catches (373), followed by the 90-mm (363) and 105-mm (307) meshes. The results of the master curve estimation showed that the larger the mesh size, the higher the total length representing the same retention probability. Therefore, the catch rate of small fish decreased with the increasing mesh size. For the 84-mm net, the 50% selection length for small fish (total length ≤ 170 mm) was estimated at 186.9 mm, which was approximately 17 mm larger than the length limit. The results show that when using tie-down gillnets, the size of the fish caught changed according to the changes in the mesh size.
How Infrared Radiation Was Discovered—Range of This Discovery and Detailed, Unknown Information
Authors: Minkina Waldemar
Published: October 2021

The reason for writing this article is that the details and mainly the scope of the fundamental discovery of infrared radiation are not widely known, and different accounts of this story are found in the literature. For example, not everyone knows that the discoverer of infrared radiation, F. W. Herschel, simultaneously studied its properties, which he, then, described in detail in his publications. It can be concluded that the history of the discovery of infrared radiation is treated marginally in the literature. This is not fair, considering the fact that infrared radiation is of fundamental importance to modern man. On the other hand, the history of the discovery of, for example, X-rays or Maxwell’s electromagnetic radiation is well known—this information is passed on to students of electrical faculties during lectures on “Fundamentals of Physics” or “Fundamentals of Electrical Engineering”. Although it is currently believed that the significance of infrared radiation for modern man is comparable to that of X-rays, when I ask the students during lectures who discovered infrared radiation and how, there is usually a deafening silence.
An Aerosol Sensor for Multi-Sized Particles Detection Based on Surface Acoustic Wave Resonator and Cascade Impactor
Authors: Chen Zhiyuan , Liu Jiuling , Liu Minghua , You Ran , He Shitang
Published: October 2021

This research proposed the design, fabrication, and experiments of a surface acoustic wave resonator (SAWR)-based multi-sized particles monitor. A wide range selection and monitoring of large coarse particles (LCP), inhalable particles (PM10), and fine inhalable particles (PM2.5) were achieved by combining high-performance 311 MHz SAWRs and a specially designed cascade impactor. This paper calculated the normalized sensitivity distribution of the chip to the mass loading effect, extracted the optimal response area for particle attachment, analyzed the influence of the distance between nozzle and chip surface on the particle distribution, and evaluated the collection efficiency of the specially designed 2 LPM (L/min) impactor through computational fluid dynamics simulation software. An experimental platform was built to conduct the response experiment of the sensor to particle-containing gas generated by the combustion of leaf fragments and repeatability test. We verified the results of the particle diameter captured at each stage. This research suggests that the sensor’s response had good linearity and repeatability, while the particles collected on the surface of the SAWR in each impactor stage met the desired diameter, observed through a microscope.
The Electromagnetic Shielding of Optoelectronic Devices by Mesh Structures
Authors: Khodzitsky Mikhal K. , Bassarab Vladimir V. , Shakhmin Alexey A. , Sokolov Valentin S. , Kropotov Grigory I.
Published: October 2021

In this work, the shielding properties of mesh structures with various cell sizes on a K108 glass substrate are studied. The transmission spectra of the samples were obtained in a frequency range from 1 GHz to 1620 THz. A comparison of the experimental transmission spectra with those obtained using several theoretical models, and a numerical calculation were carried out. The most optimal theoretical model used to describe the shielding properties of a mesh structure in the frequency range upper-bounded by a resonant frequency is the one-mode calculation model. Anti-reflection coatings were used to increase the transmission coefficient of the structures in the visible and near-IR spectral ranges. These mesh structures can be used to shield optoelectronic devices such as a video camera or a laser rangefinder from microwaves.
Environmental Impact of Discharge Patterns and Ambient Wind on the Jet Discharge from a Mechanical Upper Vent of a Tunnel
Authors: Zhang Xin , Wu Ke , Zhu Kai
Published: October 2021

Flow characteristics and pollutant dispersion characteristics of a mechanical upper vent of a tunnel under various discharge patterns and ambient wind were studied by using the computational fluid dynamics (CFD) numerical method and an experimental model. On this basis, variations in the environmental impact radius rcriti changing with the ambient wind velocity U for pollutants from vertical and horizontal outlets were also analyzed with the set discharge capacity. According to our findings, the pollutant emission of the upper vent under a vertical discharge pattern can be considered as free buoyant jet diffusion under the impact of the momentum of ambient wind, while the emission under the horizontal discharge pattern can be regarded as semi-confined buoyant jet diffusion under the impact of the momentum of ambient wind. Moreover, the rcriti of the vertical outlet increased with the increase of U when U ≤ 3 m/s and was minimally affected by U for U > 3 m/s. Additionally, the rcriti of the horizontal outlet decreased with the increase of U. When the discharge capacity was constant, the rcriti of the upper vent under both vertical and horizontal discharge patterns declined with the increase of the discharge velocity V0. Note that the rcriti of the vertical outlet was smaller than that of the horizontal one for the range of parameters considered. These results can provide a theoretical reference for optimizing the design of a vent on the top of an urban tunnel.
Quantifying the Contribution of LUCC to Surface Energy Budget: A Case Study of Four Typical Cities in the Yellow River Basin in China
Authors: Chi Qian , Zhou Shenghui , Wang Lijun , Zhu Mengyao , Liu Dandan , Tang Weichao , Zhao Xiao , Xu Siqi , Ye Siyu , Lee Jay , Cui Yaoping
Published: October 2021

With social changes and economic development, human activities inevitably lead to significant changes in land use types. Land use and land cover change (LUCC) leads to a series of changes in energy balance and surface temperature, which has an impact on the regional climate. In this study, MODIS remote sensing data were used to quantify the results of the biological and geophysical effects caused by LUCC in four typical cities in the Yellow River Basin of China: Jinan, Zhengzhou, Lanzhou and Xining. The results showed the following: (1) The latent heat flux and the net radiation of the four cities were both increasing on the whole. The latent heat flux of water and forest was higher, which played a key role in energy consumption on the ground. The net radiation value of the old urban and urban expansion areas was higher, while that of the forest was lower, which indicated that human activities increased the input of surface energy. (2) The differences between latent heat flux and net radiation in areas greatly affected by human activities were much smaller than those in natural areas such as forest and grassland. This indicted that human activities increased the warming trend. In addition, most of the differences between latent heat flux and net radiation in the four cities showed a downward trend. (3) Different cities have different regulating factors for land surface temperature (LST). In Jinan and Zhengzhou, the regulation of LST by net radiation was more obvious, while in Lanzhou and Xining, the regulation of LST by latent heat flux was more pronounced. By comparing LUCC and the forced balance between energy intake and consumption in four typical cities along the Yellow River Basin, this study emphasizes the difference of energy budgets under different land use types, which has important reference value for judging the spatial difference of urban thermal environments.
Smog Pollution, Environmental Uncertainty, and Operating Investment
Authors: Li Bin , Shi Hanxuan , Yang David C. , Peng Muze
Published: October 2021

Smog pollution in China has drawn worldwide attention. Using companies’ data from Chinese Securities Markets and Accounting Research database (CSMAR) and air quality monitoring data from China National Environmental Monitoring Centre(CNEMC), we employ the PM2.5 concentration as a proxy for smog pollution and examine the effect of smog pollution on company environmental uncertainty and operating investment in 74 key cities in China. The empirical results show that smog pollution causes an increase in company environmental uncertainty and a decrease in operating investment for Chinese listed companies, with environmental uncertainty as a mediating variable. Smog pollution can positively influence companies’ environmental uncertainty through their employees and high pressure from the public and government. According to the real-options-based investment approach, companies choose to “wait and see” and, correspondingly, reduce operating investment under high environmental uncertainty such as that caused by smog pollution. Additionally, we find that state-owned enterprises are more significantly influenced by smog pollution in terms of environmental uncertainty and operating investment because of their close relationships with the government and their responsibility to set an example among Chinese companies in the fight against smog pollution.
Modeling Multi-Dimensional Public Opinion Process Based on Complex Network Dynamics Model in the Context of Derived Topics
Authors: Chen Tinggui , Yin Xiaohua , Yang Jianjun , Cong Guodong , Li Guoping
Published: October 2021

With the rapid development of the Internet, the speed with which information can be updated and propagated has accelerated, resulting in wide variations in public opinion. Usually, after the occurrence of some newsworthy event, discussion topics are generated in networks that influence the formation of initial public opinion. After a period of propagation, some of these topics are further derived into new subtopics, which intertwine with the initial public opinion to form a multidimensional public opinion. This paper is concerned with the formation process of multi-dimensional public opinion in the context of derived topics. Firstly, the initial public opinion variation mechanism is introduced to reveal the formation process of derived subtopics, then Brownian motion is used to determine the subtopic propagation parameters and their propagation is studied based on complex network dynamics according to the principle of evolution. The formula of basic reproductive number is introduced to determine whether derived subtopics can form derived public opinion, thereby revealing the whole process of multi-dimensional public opinion formation. Secondly, through simulation experiments, the influences of various factors, such as the degree of information alienation, environmental forces, topic correlation coefficients, the amount of information contained in subtopics, and network topology on the formation of multi-dimensional public opinion are studied. The simulation results show that: (1) Environmental forces and the amount of information contained in subtopics are key factors affecting the formation of multi-dimensional public opinion. Among them, environmental forces have a greater impact on the number of subtopics, and the amount of information contained in subtopics determines whether the subtopic can be the key factor that forms the derived public opinion. (2) Only when the degree of information alienation reaches a certain level, will derived subtopics emerge. At the same time, the degree of information alienation has a greater impact on the number of derived subtopics, but it has a small impact on the dimensions of the final public opinion. (3) The network topology does not have much impact on the number of derived subtopics but has a greater impact on the number of individuals participating in the discussion of subtopics. The multidimensional public opinion dimension formed by the network topology with a high aggregation coefficient and small average path length is higher. Finally, a practical case verifies the rationality and effectiveness of the model proposed in this paper.