bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Study and Calculation Methods of Shear Capacity for High-Strength Reinforced Concrete Full-Scale Deep Beams
Authors: Li Shushan , Wu Ziwen , Zhang Junhong , Xie Wei
Published: September 2022

The shear behavior of 8 high-strength concrete full-scale deep beams with high-strength steel bars was studied. The depth beam size was 100 mm × 900 mm × 2200 mm, the test parameters included the shear span-to-depth ratio (λ = 0.9, 0.6, 0.3), longitudinal reinforcement ratio (ρs=0.66%, 1.06%, 1.26%) and stirrup reinforcement ratio (ρsv = 0, 0.26%, 0.34%, 0.5%). The ratio of the cracking load of the inclined section to the ultimate load is between 30% and 50%, and the bending deformation of the deep beam is small, showing the characteristics of brittle failure for deep beams. Under the action of a concentrated load, the failure mode of deep beams with a small shear span ratio is the failure of the diagonal compression struts, which is very different from that of shallow beams with a large shear span ratio. With the increase of shear span ratio from 0.3 to 0.9, the ultimate shear capacity of deep beams decreases by 19.33%. With the increase of longitudinal reinforcement ratio from 0.67% to 1.27%, the ultimate shear capacity of deep beams increased by 45.02%. With the increase of vertical stirrup reinforcement ratio from 0% to 0.5%, the ultimate shear capacity of deep beams increased by 8.93%. Increasing the area of longitudinal bars or stirrups limited the transverse tensile strain of the compression struts, which is conducive to improving the compressive strength of the compression struts of deep beams and then improving the bearing capacity of deep beams. The strut-and-tie model (STM) is more suitable for analyzing the shear capacity of deep beams. The calculation methods for calculating the shear capacity of deep beams were compared with ACI 318-19, CSA A23 3-19, EN 1992-1-1:2004, Tan–Tan model, Tan–Cheng model, softened STM (SSTM) and simplified SSTM (SSSTM). The results showed that the shear capacity of deep beams could be well predicted by reasonably determining the STM parameters.
Influence of Magnetic Field on Sound Transmission Loss of the Unit Filled with Magnetorheological Fluid
Authors: Xu Xiaomei , Wang Yaqin , Wang Yiwei
Published: September 2022

To explore the feasibility of applying magnetorheological fluids (MRFs) in the field of noise control, the influence of the magnetic field intensity and direction on the sound transmission loss (STL) of a unit filled with MRF (MRF unit) were investigated in this study. First, two types of test sample containing the MRF unit were designed and fabricated. The magnetic field applied to the MRF was provided by the permanent magnets used in pairs. The direction of the magnetic field was perpendicular or parallel to the direction of the sound wave propagation. The distribution of the magnetic field intensity of the two types of test samples was simulated using magnetostatic finite element analysis and validated with the magnetic field intensity measured using a Teslameter. For comparison, test samples containing air and water units were also prepared. Then, the STL of the two types of test samples were measured under different magnetic field intensities using the impedance tube method. Finally, the STL curves of the two types of test samples were presented, and the influence of magnetic field intensity and direction on the STL were discussed. The results demonstrate that the magnetic field direction has a significant influence on the STL of the MRF unit. In addition, when the magnetic field direction is parallel to the sound propagation direction, the STL of the test sample containing MRF unit significantly increases with the increase of the magnetic field intensity at low and middle frequencies.
A Novel Nonsingular Terminal Sliding Mode Observer-Based Sensorless Control for Electrical Drive System
Authors: Yang Yongjie , Liu Xudong
Published: September 2022

To improve the sensorless control performance of electrical drive systems, a nonsingular terminal sliding mode observer (NTSMO) and adaptive observer are proposed to solve the chattering and phase delay problems. Firstly, by defining a new nonsingular terminal sliding mode surface, the sliding mode observer based on the fast reaching law is designed to estimate the back electromotive force (EMF). The observer enhances the robustness and system performance eliminates the singularity and attenuates the chattering. Next, to obtain the accurate back-EMF signal, an adaptive observer is designed instead of a traditional low-pass filter to filter out the harmonics. The adaptive observer can avoid the phase delay problem and further improve the signal observation accuracy. Then, the rotor position and speed information are accurately tracked. The proposed method is applied to the speed control system of a permanent magnet synchronous motor (PMSM), and the effectiveness and feasibility of the proposed sliding mode observer are demonstrated by the experiment.
The Bivariate Unit-Sinh-Normal Distribution and Its Related Regression Model
Authors: Martínez-Flórez Guillermo , Lemonte Artur J. , Moreno-Arenas Germán , Tovar-Falón Roger
Published: September 2022

In this paper, a new bivariate absolutely continuous probability distribution is introduced. The new distribution, which is called the bivariate unit-sinh-normal (BVUSHN) distribution, arises by applying a transformation to the bivariate Birnbaum–Saunders distribution (BVBS). The main properties of the new proposal are studied in detail. In addition, from the new distribution, the BVUSHN regression model is also introduced. For both the bivariate probability distribution and the respective associated regression model, parameter estimation is conducted from a classical approach by using the maximum likelihood method together with the two-step estimation method. A small Monte Carlo simulation study is carried out to evaluate the behavior of the used estimation method and the properties of the estimators. Finally, for illustrative purposes, two applications with real data are presented in which the usefulness of the proposals is evidenced.
Utilisation of Initialised Observation Scheme for Multi-Joint Robotic Arm in Lyapunov-Based Adaptive Control Strategy
Authors: Amiri Mohammad Soleimani , Ramli Rizauddin
Published: September 2022

In this paper, we present a modelling, dynamic analysis, and controller tuning comparison for a five-degree-of-freedom (DoF) multi-joint robotic arm based on the Lyapunov-based Adaptive Controller (LAC). In most pick-and-place applications of robotic arms, it is essential to control the end-effector trajectory to reach a precise target position. The kinematic solution of the 5-DoF robotic arm has been determined by the Lagrangian technique, and the mathematical model of each joint has been obtained in the range of motion condition. The Proportional-Integral-Derivative (PID) control parameters of the LAC have been determined by the Lyapunov stability approach and are initialised by four observation methods based on the obtained transfer function. The effectiveness of the initialised controller’s parameters is compared by a unit step response as the desired input of the controller system. As a result, the average error (AE) for Ziegler–Nichols is 6.6%, 83%, and 53% lower than for Pettit & Carr, Chau, and Bucz. The performance of LAC for the robotic arm model is validated in a virtual 3D model under a robot operating system environment. The results of root mean square error by LAC are 0.021 (rad) and 0.025 (rad) for joint 1 and joint 2, respectively, which indicate the efficiency of the proposed LAC strategy in reaching the predetermined trajectory and the potential of minimizing the controller tuning complexity.
Asymptotic Behavior for the Discrete in Time Heat Equation
Authors: Abadias Luciano , Alvarez Edgardo
Published: September 2022

In this paper, we investigate the asymptotic behavior and decay of the solution of the discrete in time N-dimensional heat equation. We give a convergence rate with which the solution tends to the discrete fundamental solution, and the asymptotic decay, both in Lp(RN). Furthermore, we prove optimal L2-decay of solutions. Since the technique of energy methods is not applicable, we follow the approach of estimates based on the discrete fundamental solution which is given by an original integral representation and also by MacDonald’s special functions. As a consequence, the analysis is different to the continuous in time heat equation and the calculations are rather involved.
Degradation of Xenobiotic Pollutants: An Environmentally Sustainable Approach
Authors: Miglani Rashi , Parveen Nagma , Kumar Ankit , Ansari Mohd. Arif , Khanna Soumya , Rawat Gaurav , Panda Amrita Kumari , Bisht Satpal Singh , Upadhyay Jyoti , Ansari Mohd Nazam
Published: September 2022

The ability of microorganisms to detoxify xenobiotic compounds allows them to thrive in a toxic environment using carbon, phosphorus, sulfur, and nitrogen from the available sources. Biotransformation is the most effective and useful metabolic process to degrade xenobiotic compounds. Microorganisms have an exceptional ability due to particular genes, enzymes, and degradative mechanisms. Microorganisms such as bacteria and fungi have unique properties that enable them to partially or completely metabolize the xenobiotic substances in various ecosystems.There are many cutting-edge approaches available to understand the molecular mechanism of degradative processes and pathways to decontaminate or change the core structure of xenobiotics in nature. These methods examine microorganisms, their metabolic machinery, novel proteins, and catabolic genes. This article addresses recent advances and current trends to characterize the catabolic genes, enzymes and the techniques involved in combating the threat of xenobiotic compounds using an eco-friendly approach.
Elemental Analysis, Phytochemical Screening and Evaluation of Antioxidant, Antibacterial and Anticancer Activity of Pleurotus ostreatus through In Vitro and In Silico Approaches
Authors: Mishra Vartika , Tomar Sarika , Yadav Priyanka , Vishwakarma Shraddha , Singh Mohan Prasad
Published: September 2022

Oyster mushrooms form an integral part of many diets owing to their characteristic aroma, delicious taste and nutraceutical value. In this study, we examined oyster mushrooms by direct arc optical emission spectroscopy for the presence of various biologically important elements. Furthermore, we screened phytochemicals present in Pleurotus ostreatus by applying GC-MS. Additionally, the antioxidant, antibacterial and anticancer activities of the ethanolic extract of Pleurotus ostreatus were studied. Moreover, we docked the phytochemicals and examined their binding affinities with EGFR, PR and NF-κB proteins, which are overexpressed in breast cancer. The elemental analysis showed the presence of Fe, K, Na, Ca, Mg, Cr and Sr in the spectrum. Moreover, GC-MS data revealed the presence of 32 biologically active compounds in oyster mushrooms. The ethanolic extract displayed remarkable free radical scavenging activity (~50%) against DPPH. The mushroom has shown promising antibacterial activity against both Gram-positive (S. aureus) and Gram-negative bacteria (Pseudomonasaeruginosa, Proteus vulgaris and Proteus mirabilis). The present study also revealed that oyster mushrooms possess significant anticancer activity. The ethanolic extract inhibited the growth and proliferation of MCF-7 cells. It also induced cell shrinkage, membrane blebbing and nuclear fragmentation, resulting in apoptosis of malignant cells. The molecular docking analysis showed that ligand 15 (Linoleic acid ethyl ester), ligand 27 (Ergosta-5,7,9(11),22-tetraen-3-ol, (3. beta.,22E), ligand 28 (Stigmasta-5,22-dien-3-ol, acetate, (3. beta.,22Z), ligand 30 (Ergosta-5,7,22-Trien-3-Ol, (3. Beta.,22E) and ligand 32 (gamma. Sitosterol) exhibited better binding affinities with EGFR, PR and NF-κB proteins. This result provides a strong ground for confirmation of the in vitro anticancer effect of Pleurotus ostreatus. From the present in vitro and in silico studies, it can be concluded that Pleurotus ostreatus is a useful source of essential elements and reservoir of bioactive compounds which confer its significant antioxidant, antibacterial and anticancer properties.
Development of a Molecular Marker Based on the Mitochondrial Genome for Detection of Cyclospora cayetanensis in Food and Water Samples
Authors: Durigan Mauricio , Patregnani Emma , Gopinath Gopal R. , Ewing-Peeples Laura , Lee Chaeyoon , Murphy Helen R. , Almeria Sonia , Cinar Hediye Nese , Negrete Flavia , da Silva Alexandre J.
Published: September 2022

Cyclospora cayetanensis is a coccidian parasite that causes diarrheal illness outbreaks worldwide. The development of new laboratory methods for detection of C. cayetanensis is of critical importance because of the high potential for environmental samples to be contaminated with a myriad of microorganisms, adversely impacting the specificity when testing samples from various sources using a single molecular assay. In this study, a new sequencing-based method was designed targeting a specific fragment of C. cayetanensis cytochrome oxidase gene and developed as a complementary method to the TaqMan qPCR present in the U.S. FDA BAM Chapter 19b and Chapter 19c. The comparative results between the new PCR protocol and the qPCR for detection of C. cayetanensis in food and water samples provided similar results in both matrices with the same seeding level. The target region and primers in the protocol discussed in this study contain sufficient Cyclospora-specific sequence fidelity as observed by sequence comparison with other Eimeriidae species. The sequence of the PCR product appears to represent a robust target for identifying C. cayetanensis on samples from different sources. Such a sensitive method for detection of C. cayetanensis would add to the target repertoire of qPCR-based screening strategies for food and water samples.
Chiral Discrimination of Mexiletine Enantiomers by Capillary Electrophoresis Using Cyclodextrins as Chiral Selectors and Experimental Design Method Optimization
Authors: Cârcu-Dobrin Melania , Hancu Gabriel , Papp Lajos Attila , Fülöp Ibolya
Published: September 2022

Mexiletine (MXL) is a class IB antiarrhythmic agent, acting as a non-selective voltage-gated sodium channel blocker, used in therapy as a racemic mixture R,S-MXL hydrochloride. The aim of the current study was the development of a new, fast, and efficient method for the chiral separation of MXL enantiomers using capillary electrophoresis (CE) and cyclodextrins (CDs) as chiral selectors (CSs). After an initial CS screening, using several neutral and charged CDs, at four pH levels, heptakis-2,3,6-tri-O-methyl-β-CD (TM-β-CD), a neutral derivatized CD, was chosen as the optimum CS for the enantioseparation. For method optimization, an initial screening fractional factorial design was applied to identify the most significant parameters, followed by a face-centered central composite design to establish the optimal separation conditions. The best results were obtained by applying the following optimized electrophoretic conditions: 60 mM phosphate buffer, pH 5.0, 50 mM TM-β-CD, temperature 20 °C, applied voltage 30 kV, hydrodynamic injection 50 mbar/s. MXL enantiomers were baseline separated with a resolution of 1.52 during a migration time of under 5 min; S-MXL was the first migrating enantiomer. The method’s analytical performance was verified in terms of precision, linearity, accuracy, and robustness (applying a Plackett–Burman design). The developed method was applied for the determination of MXL enantiomers in pharmaceuticals. A computer modeling of the MXL-CD complexes was applied to characterize host–guest chiral recognition.
Rapid Classification and Recognition Method of the Species and Chemotypes of Essential Oils by ATR-FTIR Spectroscopy Coupled with Chemometrics
Authors: Truzzi Eleonora , Durante Caterina , Bertelli Davide , Catellani Benedetta , Pellacani Samuele , Benvenuti Stefania
Published: September 2022

In the present work, the applicability of attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, coupled with chemometric tools in recognizing essential oils (EOs) for routine control, was evaluated. EOs belonging to Mentha, Cymbopogon, and Lavandula families and to S. rosmarinus and T. vulgaris species were analyzed, and the performance of several untargeted approaches, based on the synergistic combination of ATR-FTIR and Partial Least Squares Discriminant Analysis (PLS-DA), was tested to classify the species and chemotypes. Different spectra pre-processing methods were employed, and the robustness of the built models was tested by means of a Receiver Operating Characteristic (ROC) curve and random permutations test. The application of these approaches revealed fruitful results in terms of sensitivity and specificity, highlighting the potentiality of ATR-FTIR and chemometrics techniques to be used as a sensitive, cost-effective, and rapid tool to differentiate EO samples according to their species and chemotype.
Hyaluronic Acid Oligosaccharide Derivatives Alleviate Lipopolysaccharide-Induced Inflammation in ATDC5 Cells by Multiple Mechanisms
Authors: Huang Hesuyuan , Ding Xuyang , Xing Dan , Lin Jianjing , Li Zhongtang , Lin Jianhao
Published: September 2022

High molecular weight hyaluronic acids (HMW-HAs) have been used for the palliative treatment of osteoarthritis (OA) for decades, but the pharmacological activity of HA fragments has not been fully explored due to the limited availability of structurally defined HA fragments. In this study, we synthesized a series glycosides of oligosaccharides of HA (o-HAs), hereinafter collectively referred to as o-HA derivatives. Their effects on OA progression were examined in a chondrocyte inflammatory model established by the lipopolysaccharide (LPS)-challenged ATDC5 cells. Cell Counting Kit-8 (CCK-8) assays and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) showed that o-HA derivatives (≤100 μg/mL) exhibited no cytotoxicity and pro-inflammatory effects. We found that the o-HA and o-HA derivatives alleviated LPS-induced inflammation, apoptosis, autophagy and proliferation-inhibition of ATDC5 cells, similar to the activities of HMW-HAs. Moreover, Western blot analysis showed that different HA derivatives selectively reversed the effects of LPS on the expression of extracellular matrix (ECM)-related proteins (MMP13, COL2A1 and Aggrecan) in ATDC5 cells. Our study suggested that o-HA derivatives may alleviate LPS-induced chondrocyte injury by reducing the inflammatory response, maintaining cell proliferation, inhibiting apoptosis and autophagy, and decreasing ECM degradation, supporting a potential oligosaccharides-mediated therapy for OA.
Mechanism of Citri Reticulatae Pericarpium as an Anticancer Agent from the Perspective of Flavonoids: A Review
Authors: Song Li , Xiong Peiyu , Zhang Wei , Hu Hengchang , Tang Songqi , Jia Bo , Huang Wei
Published: September 2022

Citri Reticulatae Pericarpium (CRP), also known as “chenpi”, is the most common qi-regulating drug in traditional Chinese medicine. It is often used to treat cough and indigestion, but in recent years, it has been found to have multi-faceted anti-cancer effects. This article reviews the pharmacology of CRP and the mechanism of the action of flavonoids, the key components of CRP, against cancers including breast cancer, lung cancer, prostate cancer, hepatic carcinoma, gastric cancer, colorectal cancer, esophageal cancer, cervical cancer, bladder cancer and other cancers with a high diagnosis rate. Finally, the specific roles of CRP in important phenotypes such as cell proliferation, apoptosis, autophagy and migration–invasion in cancer were analyzed, and the possible prospects and deficiencies of CRP as an anticancer agent were evaluated.
Glycerol Valorization—The Role of Biochar Catalysts
Authors: Gonçalves Ana R. P. , Ribeiro Ana P. C. , Orišková Sofia , Martins Luísa M. D. R. S. , Cristino Ana F. , dos Santos Rui Galhano
Published: September 2022

The conversion of renewable feedstocks into new added-value products is a current hot topic that includes the biodiesel industry. When converting vegetable oils into biodiesel, approximately 10% of glycerol byproduct is produced. Glycerol can be envisaged as a chemical platform due to its chemical versatility, as a scaffold or building block, in producing a wide range of added-value chemicals. Thus, the development of sustainable routes to obtain glycerol-based products is crucial and urgent. This certainly encompasses the use of raw carbonaceous materials from biomass as heterogeneous acid catalysts. Moreover, the integration of surface functional groups, such as sulfonic acid, in carbon-based solid materials, makes them low cost, exhibiting high catalytic activity with concomitant stability. This review summarizes the work developed by the scientific community, during the last 10 years, on the use of biochar catalysts for glycerol transformation.
Pharmaceutics 2022 Best Paper Awards
Authors:   Pharmaceutics Editorial Office
Published: September 2022

Pharmaceutics [...]
High Levels of Zinc Affect Nitrogen and Phosphorus Transformation in Rice Rhizosphere Soil by Modifying Microbial Communities
Authors: Lv Haihan , Ji Chenchen , Ding Jingli , Yu Lu , Cai Hongmei
Published: September 2022

Due to global industrialization in recent decades, large areas have been threatened by heavy metal contamination. Research about the impact of excessive Zn on N and P transformation in farmland has received little attention, and its mechanism is still not completely known. In this study, we planted rice in soils with toxic levels of Zn, and analyzed the plant growth and nutrient uptake, the N and P transformation, enzyme activities and microbial communities in rhizosphere soil to reveal the underlying mechanism. Results showed high levels of Zn severely repressed the plant growth and uptake of N and P, but improved the N availability and promoted the conversion of organic P into inorganic forms in rice rhizosphere soil. Moreover, high levels of Zn significantly elevated the activities of hydrolases including urease, protease, acid phosphatase, sucrase and cellulose, and dehydrogenase, as well as the abundances of Flavisolibacter, Sphingomonas, Gemmatirosa, and subgroup_6, which contributed to the mineralization of organic matter in soil. Additionally, toxic level of Zn repressed the nitrifying process by decreasing the abundance of nitrosifying bacteria Ellin6067 and promoted denitrification by increasing the abundance of Noviherbaspirillum, which resulted in decreased NO3− concentration in rice rhizosphere soil under VHZn condition.
Preliminary Studies on the In Vitro Interactions Between the Secondary Metabolites Produced by Esca-Associated Fungi and Enological Saccharomyces cerevisiae Strains
Authors: Scarano Leonardo , Mazzone Francesco , Mannerucci Francesco , D’Amico Margherita , Bruno Giovanni Luigi , Marsico Antonio Domenico
Published: September 2022

Esca-affected vines alter the carbohydrate metabolism, xylem transport of water and photosynthesis and show regular grapes (but berries do not reach maturity), and phenolic compounds are reduced in concentration, oxidate and polymerizate. Pullulan and a mixture of scytalone and isosclerone (9:1; w/w), secondary metabolites produced in vitro and in planta by Phaeoacremonium minimum (syn. P. aleophilum) and Phaeomoniella chlamydospora, were assayed against the strains Byosal HS1 and IOC 18-2007 in microvinifications with synthetic grape must. The presence of pullulan and pentaketides mix affects the growth and metabolism of the tested Saccharomyces cerevisiae strains. Assays at 100 and 1000 µg mL−1 inhibited the growth of both strains, while no effects were recorded when evaluated at 1 and 5 µg mL−1. In comparison with the controls, pullulan and the scytalone/isosclerone mixture at 10 µg mL−1 had a growth reduction, a lower alcohol yield, reduced the concentration of tartaric acid and malic acid; and slowed down the production of lactic acid, acetic acid and total polyphenol content of the tested S. cerevisiae strains. These metabolites could be applied as an alternative to the sulfite addition in the early stages of vinification to support the action of selected Saccharomyces. Appealing is the subtractive action of pullulan against tartaric acid. Further data are needed to confirm and validate the enological performance in freshly pressed grape juice.
Effects of Injection Timing and Injection Volume on the Combustion and Emissions of a Two-Stroke Kerosene Direct Injection Engine
Authors: Bei Taixue , Lu Bo , Liu Rui , Huang Junhui , Zhang Bing
Published: September 2022

To study the influence of injection time and injection volume on the working process of a two-stroke kerosene direct injection engine, an experimental study was carried out on an improved two-stroke inline three-cylinder gasoline engine, combined with calculations and analysis with GT-POWER and AVL FIRE software. The results showed that when the injection end angle increased from 50° to 70° before the top dead center (BTDC), the average pressure and temperature in the cylinder increased rapidly, the peak value of pressure and temperature and the cumulative heat release increased, and the combustion process in the cylinder was more sufficient. The fuel injection volume was set to 7.5 mg, 8 mg, and 8.5 mg. With increasing fuel injection volume, the average pressure and average temperature first increased and then decreased, the peak value gradually increased, the heat release rate and cumulative heat release increased sharply, the corresponding time gradually advanced, and the peak value gradually increased. With increasing fuel injection volume, CO, NO, and soot gradually increased, while CO2 slightly decreased.
Design of a Lightweight and Deployable Soft Robotic Arm
Authors: Palmieri Pierpaolo , Melchiorre Matteo , Mauro Stefano
Published: September 2022

Soft robotics represents a rising trend in recent years, due to the ability to work in unstructured environments or in strict contact with humans. Introducing soft parts, robots can adapt to various contexts overcoming limits relative to the rigid structure of traditional ones. Main issues of soft robotics systems concern the relatively low force exertion and control complexity. Moreover, several fields of application, as space industry, need to develop novel lightweight and deployable robotic systems, that can be stored into a relatively small volume and deployed when required. In this paper, POPUP robot is introduced: a soft manipulator having inflatable links and rigid joints. Its hybrid structure aims to match the advantages of rigid robots and the useful properties of having a lightweight and deployable parts, ensuring simple control, low energy consumption and low compressed gas requirement. The first robot prototype and the system architecture are described highlighting design criteria and effect of internal pressure on the performances. A pseudo-rigid body model is used to describe the behavior of inflatable links looking forward to control design. Finally, the model is extended to the whole robot: multi-body simulations are performed to highlight the importance of suitable sensor equipment for control development, proposing a visual servoing solution.
A LTCC-Based Ku-Band 8-Channel T/R Module Integrated with Drive Amplification and 7-Bit True-Time-Delay
Authors: Liu Xiao , Zeng Qinghua , Ding Zhengzhi , Xu Haitao
Published: September 2022

Ku-band drive amplification and a 7-bit true-time-delay (TTD) function were realized as a part of a LTCC-based T/R module to increase integration. The 8-channel T/R module was fabricated and its key characteristics were measured, including a 3-bit (1/2/4 λ) TTD, 4-bit (0.25/0.5/1/2 λ) TTD, receive gain, noise figure and output power. The 8-channel T/R module can be further adopted to increase bandwidth and scanning angle of phased arrays without beam squint.
Small Target Recognition and Tracking Based on UAV Platform
Authors: Tian Xiangrui , Jia Yinjun , Luo Xin , Yin Jie
Published: September 2022

Target recognition and tracking based on multi-rotor UAVs have the advantages of low cost and high flexibility. It can monitor low-altitude targets with high intensity. It has great application prospects in national defense, military, and civil fields. The existing algorithms for aerial small target recognition and tracking have the disadvantages of slow speed, low accuracy, poor robustness, and insufficient intelligence. Aiming at the problems of existing algorithms, this paper first makes a lightweight improvement for the YOLOv4 network recognition algorithm suitable for small target recognition and tests it on the VisDrone dataset. The accuracy of the improved algorithm is increased by 1.5% and the speed is increased by 3.3 times. Then, by analyzing the response value, the KCF tracking situation is judged, and the template update of the adaptive learning rate is realized. When the tracking fails, the target is re-searched and tracked based on the recognition results and the similarity judgment. Finally, experiments are carried out on the multi-rotor UAV, and the adaptive zoom tracking strategy is designed to track pedestrians, cars, and UAVs. The results show that the proposed algorithm can achieve stable tracking of long-distance small targets.
Robust Achromatic All-Dielectric Metalens for Infrared Detection in Intelligent Inspection
Authors: Si Wenrong , Hu Zhengyong , Lan Dun , Zhou Yi , Li Wei
Published: September 2022

Metalens has the advantages of high design freedom, light weight and easy integration, thus provides a powerful platform for infrared detection. Here, we numerically demonstrated a broadband achromatic infrared all-dielectric metalens over a continuous 800 nm bandwidth, with strong environmental adaptability in air, water and oil. By building a database with multiple 2π phase coverage and anomalous dispersions, optimizing the corrected required phase profiles and designing the sizes and spatial distributions of silicon nanopillars, we numerically realized the design of broadband achromatic metalens. The simulation results of the designed metalens show nearly constant focal lengths and diffraction-limited focal spots over the continuous range of wavelengths from 4.0 to 4.8 μm, indicating the ability of the designed metalens to detect thermal signals over a temperature range from various fault points. Further simulation results show that the metalens maintains good focusing performance under the environment of water or oil. This work may facilitate the application of metalens in ultra-compact infrared detectors for power grid faults detection.
Coherence Function and Adaptive Noise Cancellation Performance of an Acoustic Sensor System for Use in Detecting Coronary Artery Disease
Authors: Fynn Matthew , Nordholm Sven , Rong Yue
Published: September 2022

Adaptive noise cancellation is a useful linear technique to attenuate unwanted background noise that cannot be removed using traditional frequency-selective filters. Usually, this is due to the signal and noise co-existing in the same frequency band. This paper tests a weighted least mean squares (WLMS) algorithm on a stethoscope system for use in detecting coronary artery disease in the presence of background noise. Each stethoscope is equipped with two microphones: one used to detect heart signals and one used to detect background noise. The WLMS method was used for four different sources of background noise whilst measuring a heartbeat, including a single tone, multiple tones, hospital/clinic noise, and breathing noise. The magnitude-squared coherence between both microphones was unity for the tone scenarios, resulting in complete attenuation. For the other background noise sources, a less-than-unity magnitude-squared coherence resulted in minor and no attenuation. Thus, the coherence function is a tool that can be used to predict the amount of attenuation achievable by linear adaptive noise-cancellation techniques, such as WLMS, as presented in this article.
MEST: An Action Recognition Network with Motion Encoder and Spatio-Temporal Module
Authors: Zhang Yi
Published: September 2022

As a sub-field of video content analysis, action recognition has received extensive attention in recent years, which aims to recognize human actions in videos. Compared with a single image, video has a temporal dimension. Therefore, it is of great significance to extract the spatio-temporal information from videos for action recognition. In this paper, an efficient network to extract spatio-temporal information with relatively low computational load (dubbed MEST) is proposed. Firstly, a motion encoder to capture short-term motion cues between consecutive frames is developed, followed by a channel-wise spatio-temporal module to model long-term feature information. Moreover, the weight standardization method is applied to the convolution layers followed by batch normalization layers to expedite the training process and facilitate convergence. Experiments are conducted on five public datasets of action recognition, Something-Something-V1 and -V2, Jester, UCF101 and HMDB51, where MEST exhibits competitive performance compared to other popular methods. The results demonstrate the effectiveness of our network in terms of accuracy, computational cost and network scales.
Do Neighborhood Factors Modify the Effects of Lead Exposure on Child Behavior?
Authors: Frndak Seth , Barg Gabriel , Queirolo Elena I. , Mañay Nelly , Colder Craig , Yu Guan , Ahmed Zia , Kordas Katarzyna
Published: September 2022

Lead exposure and neighborhoods can affect children’s behavior, but it is unclear if neighborhood characteristics modify the effects of lead on behavior. Understanding these modifications has important intervention implications. Blood lead levels (BLLs) in children (~7 years) from Montevideo, Uruguay, were categorized at 2 µg/dL. Teachers completed two behavior rating scales (n = 455). At one-year follow-up (n = 380), caregivers reported child tantrums and parenting conflicts. Multilevel generalized linear models tested associations between BLLs and behavior, with neighborhood disadvantage, normalized difference vegetation index (NDVI), and distance to nearest greenspace as effect modifiers. No effect modification was noted for neighborhood disadvantage or NDVI. Children living nearest to greenspace with BLLs < 2 µg/dL were lower on behavior problem scales compared to children with BLLs ≥ 2 µg/dL. When furthest from greenspace, children were similar on behavior problems regardless of BLL. The probability of daily tantrums and conflicts was ~20% among children with BLLs < 2 µg/dL compared to ~45% among children with BLLs ≥ 2 µg/dL when closest to greenspace. Furthest from greenspace, BLLs were not associated with tantrums and conflicts. Effect modification of BLL on child behavior by distance to greenspace suggests that interventions should consider both greenspace access and lead exposure prevention.
Human Health Risks and Air Quality Changes Following Restrictions for the Control of the COVID-19 Pandemic in Thailand
Authors: Kaewrat Jenjira , Janta Rungruang , Sichum Surasak , Rattikansukha Chuthamat , Tala Wittaya , Kanabkaew Thongchai
Published: September 2022

The coronavirus (COVID-19) pandemic first impacted Thailand in early 2020. The government imposed lockdown measures from April to May 2020 to control the spread of infection. Daily lifestyles then morphed into a so-called new normal in which activities were conducted at home and people avoided congregation in order to prevent the spread of an infectious disease. This study evaluated the long-term air quality improvement which resulted from the restrictions enforced on normal human activities in Thailand. The air quality index (AQI) of six criteria pollutants and health risk assessments were evaluated in four areas, including metropolitan, suburban, industrial, and tourism areas in Thailand. The results showed that, after the restriction measures, the overall AQI improved by 30%. The subindex of each pollutant (sub-AQI) of most pollutants significantly improved (by 30%) in metropolitan areas after human activities changed due to the implementation of lockdown measures. With regard to industrial and tourism areas, only the sub-AQI of traffic-related pollutants decreased (34%) while the sub-AQIs of other pollutants before and after lockdown were similar. However, the changes in human activities were not clearly related to air quality improvement in the suburban area. The overall hazard index (HI) after lockdown decreased by 23% because of the reduction of traffic-related pollutants. However, the HI value remained above the recommended limits for the health of the adult residents in all areas. Therefore, strict regulations to control other pollutant sources, such as industry and open burning, will also be necessary for air quality improvement in Thailand.
FAKTOR-FAKTOR YANG MEMPENGARUHI STRESS DAN KECEMASAN PADA PASIEN PENYAKIT GINJAL KRONIK DENGAN HEMODIALISIS
Authors: Nurhayati Farial , Ritianingsih Nieniek
Published: September 2022

Prevalensi PGK meningkat seiring meningkatnya jumlah penduduk usia lanjut dan kejadian penyakit diabetes melitus serta hipertensi. Pada derajat awal, PGK belum menimbulkan gejala dan tanda, bahkan hingga laju filtrasi glomerulus sebesar 60% pasien masih asimtomatik namun sudah terjadi peningkatan kadar urea dan kreatinin serum. Hemodialisa merupakan salah satuterapi untuk pengganti fungsi ginjal, selain itu terdapat terapi pengganti seperti peritonial dialisa, dan transplantasi ginjal. Pasien merasa penyakitnya sulit disembuhkan dan perjalanan penyakit yang mengharuskan menjalani terapi hemodialisa membuat pasien merasa tidak nyaman. Ketidaknyamanan pada pasien hemodialisis dapat berupa stress dan kecemasan. Penelitian ini bertujuan untuk menegtahui faktor-faktor yang berhubungan dengan stress dan kecemasan pada pasien penyakit ginjal kronik dengan hemodialisis. Metode yang digunakan dalam penelitian ini adalah deskriptif kuantitatif dengan desain crosssectional. Subjek dari penelitian ini adalah pasien penyakit ginjal kronik dengan hemodialisis jumlah sampel 82 responden. Stres dan kecemasan diukur dengan menggunakan skala kuesioner DASS-42. Hasil penelitian tidak ada hubungan factor-faktor jenis kelamin, tingkat Pendidikan, penghasilan dan lama hemodialissis dengan kecemasan dan stress pada pasien penyakit ginjal kronik dengan hemodialisis.
Formação continuada e suas contribuições para o desenvolvimento profissional de professores
Authors: Da Silva Gabrriel Fernandes , Seabra Michelle Ariane de Lima , Miguel Maria Elisabeth Blanck
Published: September 2022

Este trabalho tem como pressuposto que o professor é um personagem central para o bom êxito do processo de ensino-aprendizagem, assim como sua formação e os documentos que a orientam. O objetivo geral é compreender como o processo de formação continuada melhora a atuação do professor. Responde aos seguintes objetivos específicos: verificar como ocorre a formação continuada do professor; identificar como essa formação contribui para a melhor atuação do professor no processo de ensino-aprendizagem e verificar a articulação de tal formação aos documentos normativos. A metodologia escolhida para sua realização foi o estudo de caso, pois a investigação foi realizada em uma única escola, na cidade de Curitiba/PR. Os procedimentos utilizados para coleta de dados foram: aplicação de questionário e levantamento documental. Para auxiliar a análise dos dados coletados, utilizou-se Sacristán (2001), Marques (2003), Garcia (1999), Perrenoud (1993), Stahlschmidt (2009), Costa e Antunes (2008), além dos documentos oficiais que tratam da formação continuada do professor. A análise dos dados coletados indica que os professores que participam do processo de formação continuada, apropriam-se de técnicas para elaboração de planos de aula, atualizam os seus conhecimentos e sua metodologia de ensino. Todavia, as fontes revelam que alguns professores não procuram os cursos de formação continuada por motivos financeiros e porque estes cursos ocorrem em lugares distantes das escolas em que lecionam. Além disso, outro motivo indicado é a ausência de estímulos e benefícios à progressão da carreira docente, uma vez que a participação nessas qualificações deveria ser considerada para promoções na carreira dos professores, como dispõe a meta 16 do Plano Nacional de Educação (2014-2024). Em razão do congelamento do teto de gastos públicos por meio da P.E.C 241 (Congresso Nacional) e da P.E.C 55(Senado Federal), aprovadas em 2016, a área da educação, entre outras, não pode considerar a progressão e incorporação desses cursos à carreira docente.
Perfil epidemiológico da Hanseníase na microrregião da planície litorânea do Piauí
Authors: Maximiano Hyorranne Raysa Lima , Fernandes Francisco Leonardo de Souza , Araújo Francisco Carlos Junio Linhares Costa , Farias Flávio Furtado de
Published: September 2022

Objetivo: descrever o perfil epidemiológico da hanseníase em 11 municípios da planície litorânea do Piauí no período de 2010-2021, com base nos indicadores. Métodos: Trata-se de um estudo epidemiológico, descritivo, quantitativo, transversal de recorte temporal, documental, sobre o perfil epidemiológico dos casos de hanseníase na microrregião da planície litorânea do Piauí no período de 2010 a 2021, com dados coletados no Sistema de Notificação de Agravos de Notificação no período de Março a Abril de 2022. Resultados: Foram notificados 980 casos de hanseníase na microrregião da planície litorânea no período estudado, com taxa de prevalência de 3,4 casos por 10.000 habitantes para ambos os sexos, proporção de casos multibacilares:paucibacilares de 1,45, com maior número de casos notificados entre 40-49 (19,7%). A maioria dos casos apresentaram grau de incapacidade zero, mas ainda persistem 24% com grau de incapacidade I ou II. A maior ocorrência dos casos de hanseníase foi entre pessoas com baixo grau de escolaridade, 50% com ensino fundamental incompleto. Conclusão: A microrregião da planície litorânea no Piauí no período de 2010 a 2021, pode-se inferir que está ocorrendo mudança no perfil da hanseníase na região, que, no entanto, ainda permanece como de alta endemicidade, demandando esforços para que a região contribua para a eliminação da doença, especialmente, considerando-se os prejuízos relativos ao diagnóstico durante a pandemia da Covid-19. Além da implementação de políticas de atenção que considerem fatores condicionantes da saúde, tais como nível educacional, acesso aos serviços de saúde, iniquidades sociais.
Análise dos testes de intolerância alimentar A200 e correlaçao com a síndrome do intestino irritável em pacientes de um centro privado de coloproctologia
Authors: De Lara Bárbara Pereira , De Lara Ana Carolina Pereira , de Lara Leonardo Pereira Pegoraro , De Lara Maria Eduarda Pereira , Garbugio Filho Valdomiro
Published: September 2022

Introdução: A síndrome do intestino irritável (SII) é um conjunto de sinais e sintomas bastante prevalentes na população, cuja etiologia e fisiopatologia ainda não estão bem estabelecidas. Acredita-se que as intolerâncias e hipersensibilidades alimentares podem ser responsáveis por uma parte significativa dos casos. Atualmente, o tratamento da SII é baseado no alivio dos sintomas e não no agente causador da síndrome. Objetivos: realizar uma análise e fazer uma correlação entre a síndrome do intestino irritável e as alergias e hipersensibilidades alimentares. Materiais e métodos: Trata-se de um estudo longitudinal, retrospectivo, de caráter observacional, realizado através de análise de prontuários em pacientes que foram submetidos ao teste de intolerância alimentar A 200, que identifica a presença e os níveis de IgG específicas de mais de 200 proteínas de alimentos presentes na dieta mediterrânea, entre os períodos de maio de 2019 até setembro de 2020, em uma instituição privada de coloproctologia. Foi proposta a retirada da dieta os alimentos identificados no teste por um período de 90 dias e, posteriormente, avaliado a melhora clinica dos sintomas gastrointestinais da SII e extra-intestinais. Resultados: Foram avaliados 94 pacientes com diagnóstico da SII que foram submetidos ao teste de intolerância alimentar A200. Os alimentos que mais causaram algum grau de intolerância foram a cola/ noz de cola (100%), cevada (96,80%), a levedura de cerveja (95,74%), o malte (95,74%), leite/queijo de vaca (93,61%) e a clara de ovo (91,48%). Dos pacientes que apresentaram boa adesão ao tratamento proposto, 92,3% apresentaram melhora dos sintomas com a abordagem da restrição alimentar. Conclusão: os sintomas da SII podem estar associados á intolerâncias e hipersensibilidades alimentares, sua exclusão da dieta por um período de tempo, pode melhorar os sintomas da síndrome e, no futuro, modificar os tratamentos já existentes.
Adequação calórico-proteica de pacientes com COVID-19 em terapia nutricional no estado de Pernambuco
Authors: Xavier Daniel Emiliano de Farias , Souto Mylena Dias , Dourado Keila Fernandes , Aguiar Gisele Barbosa de , Andrade Maria Izabel Siqueira de , Neto João Araújo Barros , Júnior Ivanildo Ribeiro Domingos , Santos Cláudia Mota dos
Published: September 2022

O novo coronavírus humano, o SARS-CoV-2, causador da COVID-19, provocou uma pandemia mundial, gerando grande número de infectados e mortes. A terapia nutricional (TN) é parte fundamental da atenção integral à saúde do paciente com COVID-19, sendo instituída após avaliação nutricional, ofertando calorias e proteínas nas quantidades adequadas, refletindo no estado nutricional do paciente. A recomendação calórico-proteica na terapia nutricional do paciente com COVID-19 deve seguir as recomendações vigentes. O estudo em questão teve objetivo de avaliar a adequação de calorias e proteínas, comparando com o tipo de internamento e desfecho clínico de pacientes com COVID-19 submetidos a terapia nutricional no estado de Pernambuco. O estudo foi feito a partir de dados secundários, sendo analisado dados sociodemográficos, sobre comorbidades, tipo de internamento, desfecho clínico e informações relacionadas a prescrição dietética. Os cálculos de adequação calórico-proteica foram realizados a partir dos dados de prescrição dietética, comparando-os com as recomendações vigentes. A amostra foi composta por 82 pacientes com média de idade de 58,69+15,76 anos, sendo 49,4% idosos e 51,2% do sexo masculino. As comorbidades mais frequentes no grupo estudado foram hipertensão, diabetes e doenças cardiovasculares respectivamente. Em relação ao tipo de internamento, 54,9% dos pacientes da amostra estavam em internamento clínico, 17,1% em Unidade de Terapia Intensiva (UTI) e 28% não apresentavam dados disponíveis/registrados no banco de dados.   Foi demonstrado que a mediana de consumo de calorias foi 1734,00 calorias/dia (Intervalo interquartílico (IQ) 1428,00- 1997,75) e a de proteínas 110,00 gramas/dia (IQ 100,00-138,25). A mediana de adequação do consumo calórico foi de 100% (IQ 99,37- 116,00) e a de consumo proteico 87% (IQ 77-100). Pacientes em internamento clínico tiveram maiores medianas de consumo de calorias (p=0,003), maiores medianas de adequação de calorias (p=0,036) e proteínas (p=0,003) em relação aos pacientes de UTI. Os pacientes que tiveram alta/transferência apresentaram maiores medianas de consumo de proteínas (p=0,09) e adequação calórico (p=0,001) proteica (p=0,014), quando comparado aos pacientes que foram a óbito. O presente estudo revelou que pacientes com oferta calórico-proteica inadequada apresentaram pior desfecho clínico e internamento em UTI, portanto o suporte nutricional deve ser considerado como terapia adjuvante no tratamento do paciente com COVID-19, pois apresenta impactos positivos no estado clínico e consequentemente, no tipo de internamento, bem como pode influenciar o desfecho clínico desses pacientes. Assim, atingir as metas nutricionais durante a internação deve ser uma das prioridades no tratamento do paciente com COVID-19.