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Purpose: Percutaneous lesioning-techniques for treating refractory Trigeminal Neuralgias not amenable to Micro-Vascular Decompression remain useful in neurosurgical practice. Success, avoidance of complications and reduction of side-effects depend on the accurate location of the lesion-maker especially for Radio-Frequency-Thermo-Rhizotomy (RF-Th-Rh). Added to X-ray-guidance, Intra-Operative Neurophysiology can be of significant help to achieve optimal accuracy of the surgery. Based on previous research, this article aims to describe the simplest way to use direct electrical stimulation of the trigeminal root to evoke clinically observable muscle responses allowing to precisely position the tip of the needle for accurate lesioning. Technique to evoke specific localizing muscle responses: Masticatory twitches can be easily produced by stimulating the motor root, through orthodromic conduction to the masticatory muscles. Evoked Muscle Responses (EMRs) can be elicited in the facial nerve territory by stimulating the sensory rootlets, through Trigemino-Facial Reflexes' pathways (TFRs). Responses in the Orbicularis Oculi is the well-known and readily used "Blink reflex". On the contrary, TFRs in the lower territory of the facial nerve escaped clinical investigations not having been explored under direct stimulation of the trigeminal root. For both, stimulation at 5 c/s produces better observable twitches (because saccadic) than at 50 c/s which elicits tetanic contractions. Conclusion: The localizing-value of these facial EMRs (associated to evocation of paresthesias) and of the masticatory responses, justifies mapping the trigeminal root before lesioning. Their use could be extended to the other lesioning-techniques: not only Glycerol Neurolysis but also to Balloon Compression (to ascertain location of the trocar at the contact of the TGN inside the Meckel cave) and Open partial Rhizotomies (before deciding to cut the rootlets corresponding to the trigger-zone). This is of importance since lesioning-techniques are needed because not all trigeminal neuralgias are responsive to or even indications of Micro-Vascular Decompression. [ABSTRACT FROM AUTHOR]

This investigation deals with frequency analysis of an axially functionally graded material (AFGM) beam under axial temperature variations. The modeling of AFGM beam is performed using Timoshenko beam theory considering three types of axial temperature distributions. The material properties are temperature dependent and are supposed to be varied in axial direction of the beam using power law model. The beam is subjected to uniform moisture concentration to impose humidity Effect also. The Hamilton approach is employed to obtain the governing equations. The harmonic differential quadrature method is utilized to convert the derived partial differential equations to ordinary differential equations. The MATLAB code is developed to evaluate the natural frequencies of AFGM beam. The influences of temperature rise, moisture concentration, geometric index and power law index on natural frequencies of AFGM beam are explored. [ABSTRACT FROM AUTHOR]

Context: Airborne pathogens, defined as microscopic organisms, pose significant health risks and can potentially cause a variety of diseases. Given their ability to spread through diverse transmission routes from infected hosts, there is a critical need for accurate monitoring of these pathogens. This study aims to develop a sensor by investigating the vibrational responses of cantilever and bridged boundary-conditioned single-layer graphene (SLG) sheets with microorganisms, specifically SARS-CoV-2, attached at various positions on the sheet. The dynamic analysis of SLG with different boundary conditions and lengths was conducted using the atomistic finite element method (AFEM). Simulations were performed to evaluate SLG's performance as a sensor for biological entities. Altering the sheet's length and the mass of the attached biological object revealed observable frequency differences. This sensor design shows promise for enhancing the detection capabilities of graphene-based technologies for viruses. Methods: Finite element method (FEM) analysis is employed to model the sensor's performance and optimize its design parameters. The simulation results highlight the sensor's potential for achieving high sensitivity and rapid detection of SARS-CoV-2. Bridged and cantilever boundary conditions are applied at the ends of the SLG structure by using ANSYS software. Simulations have been conducted to observe how SLG behaves when used as sensors. In armchair graphene, under both boundary conditions, an SLG (5, 5) structure with a length of 50 nm displayed the highest frequency when a SARS-CoV-2 molecule with a mass of 2.6594 × 10−18 g was attached. Conversely, the chiral SLG (17, 1) structure exhibited its lowest frequency at a length of 10 nm. This insight is crucial for grasping detection limits and how factors such as size and boundary conditions influence sensor efficacy. These biosensors hold immense promise in biological sciences and medical applications, revolutionizing patient care by enabling early detection and accurate pathogen identification in clinical settings. [ABSTRACT FROM AUTHOR]

The paper presents experimental study results of self-oscillations of the current of the recombination wave (RW) type in silicon doped with impurity selenium atoms. Doping of silicon with impurity selenium atoms was carried out using a newly developed technology, which allows for the formation of nanoclusters of impurity selenium atoms in the silicon lattice consisting of Se2 and Se4 molecules, without erosion of the surface of the samples. Self-oscillations in the samples were detected at room temperature and at sufficiently low electric fields. The dependences of the RW parameters (amplitude and frequency) in the Si samples on the resistivity and concentration of the formed nanoclusters of selenium atoms, as well as on the influence of a magnetic field, which makes it possible to control the amplitude in the range of J = 10–5–5 × 10–3 A and the frequency of self-oscillations of f = 104–(5 × 106) Hz. The mechanism of the observed RWs is explained by the formation of nanoclusters consisting of two (Se2) or four (Se4) selenium atoms in silicon, which leads to the formation of fluctuations (clusters) of the main charge carriers and their reaching contact when determining the magnitude of the applied constant electric field. A possibility of practical use of self-oscillations of current observed in silicon diffusion doped with selenium impurity atoms to create solid-state generators is shown. [ABSTRACT FROM AUTHOR]

To study the efficacy and possible mechanisms of radial extracorporeal shock wave (rESW) with different frequencies for the treatment of acute skeletal muscle injury in rabbits, 48 rabbits of acute injured biceps femoris were randomly divided into 4 groups. Except for the control group, the other groups were treated by rESW with 5 Hz, 10 Hz and 15 Hz, respectively. The injury symptom index scores (ISISs) in the rESW group were significantly lower than those in the control group, with the lowest in the 10 Hz rESW group. Histomorphological features demonstrated a decrease in mononuclear cells and an increase in new myocytes across all groups, with the rESW group showing the most significant changes. The concentrations of PGE2 and IL-1β were significantly lower in all rESW groups by ELISA compared to the control group. Additionally, the 10 Hz group had lower concentrations than the 5 Hz and 15 Hz group. Compared with the control group, MyoD of the rESW groups was significantly increased, and the expression level of the 10 Hz group was higher than that of the other groups. In conclusion, rESW with 5 Hz, 10 Hz and 15 Hz take certain curative effects on acute biceps femoris injury in rabbits, and the 10 Hz rESW takes advantage over 5 Hz and 15 Hz rESW. [ABSTRACT FROM AUTHOR]

Object-based attention operates both in perception and visual working memory. While the efficient perception of auditory stimuli also requires the formation of auditory objects, little is known about their role in auditory working memory (AWM). To investigate whether attention to one object feature in AWM leads to the involuntary maintenance of another, task-irrelevant feature, we conducted four experiments. Stimuli were abstract sounds that differed on the dimensions frequency and location, only one of which was task-relevant in each experiment. The first two experiments required a match–nonmatch decision about a probe sound whose irrelevant feature value could either be identical to or differ from the memorized stimulus. Matches on the relevant dimension were detected more accurately when the irrelevant feature matched as well, whereas for nonmatches on the relevant dimension, performance was better for irrelevant feature nonmatches. Signal-detection analysis showed that changes of irrelevant frequency reduced the sensitivity for sound location. Two further experiments used continuous report tasks. When location was the target feature, changes of irrelevant sound frequency had an impact on both recall error and adjustment time. Irrelevant location changes affected adjustment time only. In summary, object-based attention led to a concurrent maintenance of task-irrelevant sound features in AWM. [ABSTRACT FROM AUTHOR]

The demand for faster and more reliable wireless communication has led to the emergence of 6G technology. One of the key features of 6G is the utilization of terahertz (THz) frequencies for data transmission, which can provide significantly higher data rates compared to previous generations. By extending the near-field sensing range, the communication distance can be increased, leading to improved coverage and performance in 6G systems. The proposed solution is achieved through the integration of metamaterials, which are artificially designed structures with unique electromagnetic properties. By incorporating metamaterials into the design of THz antennas, we can manipulate the near-field region and enhance its sensing capabilities. Near field enhancement can also be achieved through the use of reflectors, non-uniform spacing, and dielectric lenses. Plasmonic structures and chiral metamaterials are also effective. It is achieved by tailoring the electric and magnetic response of the metamaterials, which can effectively concentrate the THz radiation within the near-field region of the antenna. The proposed model reached 98.23% resolution, 92.51% sensitivity, 93.78% range, 88.58% frequency response, 94.02% directivity, 94.62% cross talk reduction. The enhanced near-field sensing range for THz antennas will have a significant impact on the performance of 6G communication systems. It will not only extend the communication distance but also improve signal quality and reduce power consumption. It will pave the way for the realization of ultra-high-speed and reliable 6G wireless communication, making it a potential game-changer in the future of telecommunications. [ABSTRACT FROM AUTHOR]

Rationale: Sexuality is a central aspect of being human that encompasses many facets. Cannabis, a widely used psychoactive substance, has been associated with various effects on sexuality. The relationship between cannabis and sexuality is complex and multifaceted, involving physiological, psychological, and social factors. Objectives: This review aims to provide an overview of the current literature on the effects of cannabis on several sexual functions, including sexual desire, arousal, orgasm, and sexual satisfaction. It also discusses the potential mechanisms underlying these effects, as well as the impact of dose and frequency of use. Results: This review has revealed a complex relationship between cannabis dosage and its influence on sexuality. It appears that the frequency of cannabis use in humans has been associated with the frequency of sexual activities. Individuals who use cannabis more frequently tend to report higher levels of sexual activity. Moreover, there is a notable gender difference in how cannabis affects sexuality. In addition, we found lower doses of cannabis to be linked to heightened sexual desire and enjoyment, whereas higher doses may lead to a decrease in sexual desire and performance. Conclusions: Overall, the association between cannabis and sexuality is complex and warrants further research to better understand the psychological and neurological mechanisms that underlie the effect of cannabis on these sexuality functions and its implications for sexual health. To advance in this endeavor, a crucial step is establishing a precise measurement of dosage in human studies. [ABSTRACT FROM AUTHOR]

LASTU is a tool for searching for Finnish language stimulus words for psycholinguistic studies. The tool allows the user to query a number of properties, including forms, lemmas, frequencies, and morphological features. It also includes two new measures for quantifying lemma and form ambiguity. The tool is written in Python and is available for Windows and macOS platforms. It is available at https://osf.io/j8v6b/. Included with the tool is a database based on a massive corpus of dependency-parsed Finnish language data crawled from the Internet (over 5 billion tokens). While LASTU has been developed for researchers working on the Finnish language, the openly available implementation can also be applied to other languages. [ABSTRACT FROM AUTHOR]

Precision engineering applications need for compliant micro positioning stages with a wide travel range, high accuracy, and a small footprint. These advantages are provided by monolithic compliant insertion stages, which have been the focus of the majority of earlier research, but they also have the significant drawback that damaged components cannot easily be replaced, necessitating a time-consuming machining process such wire electric discharge machining. A stage with a parallelogram flexure module and a modular design idea is suggested to solve these restrictions. The modular architecture makes it simple to repair damaged components. Large range voice coil actuators (VCA) power the stage. Stiffness matrix-based static and dynamic analytical models are used to assess the stage's performance, and the results of finite element analysis (FEA) are used to check the accuracy of these models. Experimental setup is built to verify the stage performance. The stage offers restricted cross-axis coupling of 15 μm in other directions to accommodate for nonlinear behaviour, and a translational motion of ± 7 mm along the working direction. The suggested stage displays a 18 Hz resonance frequency. The results reveal that the modular micro-positioning stage exhibits comparable static and dynamic performances, as well as capability for trajectory tracking, as the monolithic stage. [ABSTRACT FROM AUTHOR]

System accident that occurred in the Brazilian power grid on August 15, 2023 has been analyzed. The course of the accident, its consequences, and causes that led to significant damage to consumers have been reviewed from several perspectives, including the operation of automatic devices designed to prevent, eliminate, and minimize the consequences of emergency situations. A comparison of approaches to automatic emergency control devices in Brazil and Russia is presented. [ABSTRACT FROM AUTHOR]

We introduce a novel dataset of affective, semantic, and descriptive norms for all facial emojis at the point of data collection. We gathered and examined subjective ratings of emojis from 138 German speakers along five essential dimensions: valence, arousal, familiarity, clarity, and visual complexity. Additionally, we provide absolute frequency counts of emoji use, drawn from an extensive Twitter corpus, as well as a much smaller WhatsApp database. Our results replicate the well-established quadratic relationship between arousal and valence of lexical items, also known for words. We also report associations among the variables: for example, the subjective familiarity of an emoji is strongly correlated with its usage frequency, and positively associated with its emotional valence and clarity of meaning. We establish the meanings associated with face emojis, by asking participants for up to three descriptions for each emoji. Using this linguistic data, we computed vector embeddings for each emoji, enabling an exploration of their distribution within the semantic space. Our description-based emoji vector embeddings not only capture typical meaning components of emojis, such as their valence, but also surpass simple definitions and direct emoji2vec models in reflecting the semantic relationship between emojis and words. Our dataset stands out due to its robust reliability and validity. This new semantic norm for face emojis impacts the future design of highly controlled experiments focused on the cognitive processing of emojis, their lexical representation, and their linguistic properties. [ABSTRACT FROM AUTHOR]

The estimation of rockfall frequency for the quantitative assessment of rockfall hazard is challenging when there are not records of previous events. The aim of this study is to investigate the correlation between the rockfall frequency and the geometry of the overhanging rock blocks, at rocky slopes. The investigation takes place for seven rocky slopes along a coastal road in Northern Spain, and it is based on 15 years of rockfall data. A field survey of these slopes took place between May and June 2022, using a terrestrial laser scanner as well as ground and aerial photogrammetry from UAVs, in order to build three-dimensional digital models. Then, the geometrical attributes of the existing overhanging rocks were measured on the models. The surface area and the width of the latter were calculated. The correlation between the rockfall frequency and the sum of the overhanging areas at each slope was assessed. A good linear correlation was indicated between the normalized per slope area number of rockfalls and total overhang area (R2 = 0.9013) and between the respective normalized per unit of road length parameters (R2 = 0.9594). The magnitude-frequency relationship for the rockfall events that occurred at the seven slopes follows a power law distribution with exponent −0.65. [ABSTRACT FROM AUTHOR]

Background and aims: Windblown sand movements, i.e., wind denudation and sand burial, pose a strong selective pressure on dune vegetation. Dune plants commonly receive repeated wind denudation or sand burial. Therefore, simultaneously examining the role of sand movement intensity and frequency in shaping dune vegetation is critical for dune biodiversity conservation and ecological restoration. However, studies of this nature are rare. Methods: We studied the integrated effects of sand movement intensity and frequency on the seedling performance of a dominant semi-shrub, Artemisia ordosica, in the Mu Us sandland. We subjected A. ordosica seedlings to a total intensity of 10 cm wind denudation or sand burial treatments conducted once, twice or four times. Key results: We found, given that the total intensity of sand movement remains the same, increasing frequency and decreasing intensity per time largely improved seedling survival. Furthermore, increasing frequency and decreasing intensity per time significantly alleviated the negative effects of wind denudation, although such alleviation effect was not detected for sand burial. Seedlings of A. ordosica increased specific leaf area, root length, and biomass allocation to root to adapt to wind denudation, while they developed adventitious roots to adapt to sand burial. Conclusions: Our results demonstrate that a single heavy sand movement is more detrimental than multiple light ones to the performance of A. ordosica seedlings. Our findings suggest that windproof measures to prevent severe sand movements is necessary to allow the establishment of A. ordosica during the dune restoration process. [ABSTRACT FROM AUTHOR]

Context: Iridoviruses, a group of double-stranded DNA viruses, pose a significant threat to various aquatic animals, causing substantial economic losses in aquaculture and impacting ecosystem health. Early and accurate detection of these viruses is crucial for effective disease management and control. Conventional diagnostic methods, including polymerase chain reaction (PCR) and virus isolation, often require specialized laboratories, skilled personnel, and considerable time. This highlights the need for rapid, sensitive, and cost-effective diagnostic tools for iridovirus detection. Single-layer graphene, a two-dimensional material with unique properties like high surface area, excellent electrical conductivity, and chemical stability, has emerged as a versatile platform for biosensing applications. This paper explores the potential of employing single-layer graphene in the development of a bionanosensor for the sensitive and rapid detection of iridoviruses. The aim of the present investigation is to develop a sensor by analyzing the vibrational responses of single-layer graphene sheets (SLGS) with attached microorganisms. Graphene-based virus sensors typically rely on the interaction between the virus and the graphene surface, which lead to changes in the frequency response of graphene. This change is measured and used to detect the presence of the virus. Its high surface-to-volume ratio and sensitivity to changes in its frequency make it a highly sensitive platform for virus detection. Methods: We employ finite element method (FEM) analysis to model the sensor's performance and optimize its design parameters. The simulation results highlight the sensor's potential for achieving high sensitivity and rapid detection of iridovirus. Bridged and simply supported with roller support boundary conditions applied at the ends of SLG structure. Simulations have been performed to see how SLG behaves when used as sensors. A single-layer graphene armchair SLG (5,5) with 50-nm length exhibits its highest frequency vibration at 8.66 × 106 Hz, with a mass of 1.2786 Zg. In contrast, a zigzag-SLG with a (18,0) configuration has its lowest frequency vibration at 2.82 × 105 Hz. This aids in comprehending the thresholds of detection and the influence of factors such as size, and boundary conditions on sensor effectiveness. These biosensors can be especially helpful in biological sciences and the medical field since they can considerably improve the treatment of patients, cancer early diagnosis, and pathogen identification when used in clinical environments. [ABSTRACT FROM AUTHOR]

This paper analyzes the influence of three different shape memory alloy (SMA) wires (i.e., Ni-Ti, Cu-Al-Ni, and Cu-Zn wires) for mitigating model cable vibration. Shape memory alloy (SMA) wires because of their superelasticity or shape memory properties can promise to be one of the effective damping materials in suppressing stay cable oscillations. The investigation explores through experimental works, the capabilities of three Ni-Ti, Cu-Al-Ni, and Cu-Zn SMA wires by estimating the vibration amplitude suppression of the model stay cable. The effective location of the SMA wires on the model cable for vibration suppression was estimated in free as well as forced vibration cases. To impart free and forced vibration, respectively, in the cable, a transducer-based hammer and exciter were used. An accelerometer and data acquisition system was used to record and acquire vibration data. It is also very appropriate to ascertain which wire among one of the three SMA wires performs well. It is found that the Ni-Ti SMA wire has a better performance in vibration suppression as compared to Cu-Al-Ni and Cu-Zn wires. It is also established that the attachment of the SMA wire at the mid-length of the cable gives better vibration suppression for the first mode. [ABSTRACT FROM AUTHOR]

A new vibrating plate viscometer has been developed which is used and makes it possible to instantly and continuously measure the viscosity of a high-temperature material. This viscometer is designed for industrial use and enables one to measure the viscosity automatically to a high accuracy. This method of measuring the viscosity is currently used in various fields, such as the study of newly produced oil products, the selection of the optimal flow characteristics for various transfer conditions, and the development and improvement of preparing fuels. [ABSTRACT FROM AUTHOR]

A self-adaptive energy storage coordination control strategy based on virtual synchronous machine technology was studied and designed to address the oscillation problem caused by new energy units. By simulating the characteristics of synchronous generators, the inertia level of the new energy power system was enhanced, and frequency stability optimization was achieved. This strategy is integrated with the frequency response model of the new energy power system to improve the system's frequency regulation capability and achieve more stable and efficient operation. From the results, the damping of the system increased, the oscillation frequency decreased after a duration of about 15 s, and the system stability improved by 76.09%. The proposed strategy based on virtual synchronous generator adaptive energy storage coordination control strategy was improved by 83.25%. In addition, the proposed strategy has improved stability indicators and system completion efficiency by 40.57% and 22.21% respectively, both of which are better than the comparative strategies. As a result, this strategy significantly enhances the frequency regulation capability of the system, which has a positive effect on achieving efficient operation of the new energy power system and maintaining the stability of the power system. [ABSTRACT FROM AUTHOR]

This paper introduces the hardware implementation of Digital Pseudo-Random Number Generators (DPRNG) based on chaotic systems. First, high-performance pipeline hardware architectures, respectively, for the 3D Lorenz, 3D Chua, 3D Rossler, and 3D Chen chaotic systems are designed to increase the operating frequency. The study also includes an examination of the hardware architectures with 32-bit fixed-point and 32-bit single floating-point data precision. Second, hardware architectures of DPRNG based on a single chaotic system and the congruential generator are put forward. Third, a robust DPRNG, that mixes the 3D Lorenz, 3D Chua, 3D Rossler, and 3D Chen chaotic systems is proposed where all designed chaotic systems operate in parallel. This architecture increases pseudo-random numbers space up to 2480. The FPGA implementation of the proposed pipeline hardware architecture of the complex DPRNG can achieve a maximal operating frequency of 192.446 MHz with a high throughput of 73,899.264 Mbps. The NIST 800-22 test suite result indicates that the DPRNG produces high-quality pseudo-random bits. Consequently, the proposed DPRNG is deemed suitable for use in high-speed applications. [ABSTRACT FROM AUTHOR]

This paper reports exploratory research that considers two challenges recognised in the disaster risk reduction (DRR) community in recent years: one is the reinforcement of community-based DRR and the other is experts' prioritising high-impact/low-frequency hazards. Inquiries into stakeholders'—community members' in particular—understandings of disaster risks have been scarce. The research aimed to address these gaps by investigating communities' perceptions around community-based DRR and disaster risks. The research focused on natural water hazards, such as floods and typhoons generated due to atmospheric forcing factors, as well as tsunamis in four communities in Japan and England. A field survey of major structural mitigation solutions, non-structural measures, and community interviews revealed that community members did not necessarily find the often-used impact/frequency description of hazards helpful in developing and implementing community-based DRR activities. Such hazard-based scientific language does not necessarily correspond with the general public. The paper attempted 'the number of affected people', which was recognised by the research participants, to be applied as a tool for understanding disaster risks. [ABSTRACT FROM AUTHOR]

The aim of this article is to improve the performance of DBD excimer lamps systems for UV production. Within this framework, our approach considers two distinct directions: the geometric dimensions of the double-barrier lamp bulb and the characteristics of the power supply. To explore these directions, a sampling of 19 bulbs of different geometries is considered, and a specially designed power supply is used, capable of controlling the shape (duration and magnitude) and frequency of current pulses injected into the plasma. A dedicated test bench, including a supervisory program that drives the power supply and collects system performance data, is used to perform parametric sweeps and guarantee measurement repeatability: the set of electrical parameters is fully explored for each lamp, and each experiment is characterized by UV emission performance and electrical generator operating conditions. Multiquadric response surfaces, used to format the results of this multi-variable exploration, reveal the most efficient directions for system optimization: increasing gas volume and, at a given operating frequency, providing the shortest possible current pulses with high amplitude can increase both UV emission and conversion efficiency. [ABSTRACT FROM AUTHOR]

The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible flow. The reflection of the primary shock and its propagation within a confined domain are studied both theoretically and numerically in this research. Under the assumption of strong shock, the scaling law governing propagation of the main shock is proposed. The dimensionless frequency of reflected shock propagation is associated with the confined distance. The numerical simulation for the circular explosion problem in a confined domain is performed for validation. Under the influence of confinement, the principal shock wave systematically undergoes reflection within the domain until it weakens, leading to the non-monotonic attenuation of kinetic energy in the explosion fireball and periodic oscillations of the fireball volume with a certain frequency. The simulation results indicate that the frequency of kinetic energy attenuation and the volume oscillation of the explosive fireball align consistently with the scaling law. [ABSTRACT FROM AUTHOR]

Changes in context influence the way we form and structure memories. Yet, little is known about how qualitatively different types of context switches shape memory organization. The current experiments characterize how different features of context change influence the structure and organization of free recall. Participants completed a context switching paradigm in which we manipulated the rate of switches and prior experience with the contexts participants were switching between (repeated vs. novel). We measured free-recall performance and determined the extent to which participants organized items by the order in which they were encoded or the type of context with which they were originally presented. Across two experiments, we found and replicated that rapidly switching to novel, but not repeated contexts, impaired memory recall performance and biased memory towards a greater reliance on temporal information. Critically, we observed that these differences in performance may be due to distinctions in how participants organize their recalls when rapidly switching contexts. Results indicated that participants were less likely to only cluster their responses by the same context when the contexts were repeating at a high rate, as compared to when the contexts were novel. Overall, our findings support a model in which contextual familiarity rescues the costs associated with rapidly switching to new tasks or contexts. [ABSTRACT FROM AUTHOR]

Background: Frequency discrimination underlies more complicated auditory activities like speech comprehension and interpretation. However, intensity differences indicate how far apart noises are. This study aimed to evaluate and compare results of frequency modulation and difference limen for intensity in children with cochlear Implants (CI) as well as normal hearing children. Results: This case–control work was performed on 40 children, aged from 5–18 years, divided into two equal groups: a study group with unilateral CI and a control group with normal peripheral hearing. All patients were subjected to otological examination, audiological evaluation, frequency modulation difference limen (FMDL) and difference limen for intensity (DLI) tests. Patients with CI, as compared to normal hearing (NH) subjects, required significantly higher frequencies to discriminate FMDL and DLI respectively (P value = 0.001). At 2000 and 4000 Hz: FMDL had a significant diagnostic power for patients with CI (AUC = 0.980, 0.998 respectively, P < 0.001), at cut off 1.5, with 100% sensitivity and 100% specificity. While, at 4000 Hz: DLI had a significant diagnostic power for patients with CI (AUC = 0.999, P < 0.001), at cut off 1.5, with 100% sensitivity and 100% specificity. Conclusion: A statistically substantial variation was observed among CI and NH children in FMDL and DLI at all frequencies tested. Patients with CI required significantly higher frequencies to discriminate as compared to NH subjects. Frequencies at 2000 Hz and 4000 Hz possess the best specificity and sensitivity of FMDL. While frequency 4000 Hz possess the best specificity and sensitivity of DLI. [ABSTRACT FROM AUTHOR]

In this work, the abilities of Ni-C38, Ni-B19N19 and Ni-Si38 for oxygen reduction reaction (ORR) are investigated. The Eformation of Ni-C38, Ni-B19N19 and Ni-Si38 are −4.72, −5.96 and − 6.43 eV. The Ni-Si38 has higher ability to adsorb the ORR species than Ni-C38 and Ni-B19N19. The mechanism 1 is acceptable pathway for oxygen reduction reaction (ORR) on Ni-C38, Ni-B19N19 and Ni-Si38. The ΔGreaction of HO*-catalyst-O* → O* on Ni-C38, Ni-B19N19 and Ni-Si38 are −1.55, −1.59 and − 1.72 eV. The ΔGreaction of ORR on Ni-C38, Ni-B19N19 and Ni-Si38 are more negative than ΔGreaction of ORR on Pt-based catalysts, Si nanocages and C nanocages in previous works. The overpotential of ORR on Ni-C38, Ni-B19N19 and Ni-Si38 are 0.31, 0.36 and 0.42 V which are lower than overpotential of ORR on Pt catalysts. [ABSTRACT FROM AUTHOR]

In recent times, there has been a growing interest in the production of environmentally friendly materials. One area of focus is the use of polymer composites reinforced with natural fibres to replace synthetic fibres that are commonly used in structural applications. The study utilised compression moulding to create six different combinations of banana/epoxy composites. This was achieved by varying the weight fraction and length of the banana fibres used. Initially, the banana fibres were cut into chips of varying lengths—10 mm, 20 mm and 30 mm. The composition of fibre reinforcement was then altered using two different weight fractions—5% and 10%. The study aimed to investigate the effect of fibre composition and fibre length on the properties of composites by performing tensile, flexural, and acoustic tests. The tensile test results showed that the composite fabricated with 20 mm fibre length and 10% fibre composition had the highest load-bearing capacity and showed higher resistance to tensile loading. On the other hand, the three-point bending test results revealed that the composite fabricated with 5% fibre composition and 30 mm fibre length had the highest flexural load-bearing capacity. The specimens that were fractured during mechanical testing were analysed using scanning electron microscopy to understand their failure mechanisms. The impedance tube method was employed to study the influence of fibre length and volume content on the acoustic behaviour of the banana/epoxy composite. The acoustic results demonstrated that the composite fabricated with 5% fibre composition and 10 mm fibre length had the highest sound absorption coefficient value (α = 0.997), which indicates good sound insulation properties. [ABSTRACT FROM AUTHOR]

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Rayleigh-type surface waves propagating in a magneto-elastic half-space containing voids are studied. Dispersion equation is derived under suitably constructed boundary conditions, which involves elastic, electro-magnetic, void parameters and angular frequency, but contains radicals, making it difficult to solve analytically. However, under limiting frequencies, the dispersion equation is analyzed and discussed. The effect of various parameters on phase velocity of propagating Rayleigh-type surface waves is investigated and shown graphically for a particular model. The effect of induced electric field on considered surface waves is also studied and explained. It is shown that the particles near the boundary surface move in an elliptic manner. However, if there is no phase difference between the displacement components, then we have a degenerate case. Some special cases of dispersion relation are also deduced from the present formulation. [ABSTRACT FROM AUTHOR]

Fe–Cr alloys are widely used in power, petroleum, and manufacturing industries for their good resistance to corrosion and oxidation at high temperatures. Ultrasound is the only nondestructive method so far to measure the residual stress of in-service components. However, for parts with material anisotropy, such as materials processed by rolling, the measurement accuracy is highly restrained. In this paper, a rolled 316L stainless steel sample is used to study the influence of texture on the measurement of residual stress by ultrasonic surface wave. The experimental results show that the propagation velocity of surface waves in the sample has anisotropic characteristics. The wave velocity parallel to the rolling direction (0°) is the maximum, and the wave velocity perpendicular to the rolling direction (90°) is the minimum, thereby affecting the measurement accuracy. It is found that reducing the frequency of surface waves can reduce the influence of anisotropy. Therefore, a low-frequency method and modified formula are used to improve the measurement accuracy. The maximum error in the rolling direction is reduced from 21.3 to 3.6 MPa, and the maximum relative error is also reduced from 45.4 to 9.0%. The modified formula can further reduce the influence of anisotropy, with the maximum error value further reduced to 2.3 MPa, the maximum relative error reduced to 4.9%, and the surface wave detection accuracy effectively improved. [ABSTRACT FROM AUTHOR]

In the work, research was carried out on filamentous silicon crystals doped with boron admixture to concentrations corresponding to the metal–insulator transition (MIT) in silicon, as well as with an admixture of the transition metal nickel. Investigations were conducted at cryogenic temperatures in the interval 4.2–70 K using alternating current in the frequency range from 10 Hz to 250 kHz. Different conduction mechanisms have been established according to Jonscher's power law as σ(ω) ≈ Aωn. In the low-frequency range up to 20 kHz a quantum–mechanical tunneling mechanism is observed for the conduction for temperatures 4.2–30 K with a frequency-dependent coefficient n that is proportional ω0.8, which with increasing frequency to 250 kHz increases to values n ≈ ω1.8. In this case, the low-temperature conductivity increases linearly according to the superlinear power law (SLPL). [ABSTRACT FROM AUTHOR]

Studies on perception and cognition require sound methods allowing us to disentangle the basic sensory processing of physical stimulus properties from the cognitive processing of stimulus meaning. Similar to the scrambling of images, the scrambling of auditory signals is aimed at creating stimulus instances that are unrecognizable but have comparable low-level features. In the present study, we generated scrambled stimuli of short vocalizations taken from the Montreal Affective Voices database (Belin et al., Behav Res Methods, 40(2):531–539, 2008) by applying four different scrambling methods (frequency-, phase-, and two time-scrambling transformations). The original stimuli and their scrambled versions were judged by 60 participants for the apparency of a human voice, gender, and valence of the expressions, or, if no human voice was detected, for the valence of the subjective response to the stimulus. The human-likeness ratings were reduced for all scrambled versions relative to the original stimuli, albeit to a lesser extent for phase-scrambled versions of neutral bursts. For phase-scrambled neutral bursts, valence ratings were equivalent to those of the original neutral burst. All other scrambled versions were rated as slightly unpleasant, indicating that they should be used with caution due to their potential aversiveness. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) are important precipitation systems in China. Although extreme precipitation due to TCs can cause huge economic losses and human casualties, it recharges water sources and alleviates water crisis. To better assess the impact of TCs on China, the TC-affected areas were divided into eight regions and TC-induced precipitation was separated from total precipitation (1971–2020). The spatiotemporal characteristics of TC precipitation amount (TCPA), TC precipitation frequency (TCPF), and TC precipitation intensity were obtained using time-series analysis and spatial interpolation. TCs affect the coastal areas as well as inland parts of central and western China. The annual average TCPA was less than 10 mm/annum in North China, Northwest China, and Southwest China, whereas it exceeded 100 mm/annum in South China (SC) and southern part of East China (SPEC). During 1991–2020, the TCPA in northern part of East China and SPEC exhibited an upward trend, reaching 16.41 and 13.78 mm/per decade, respectively, while it demonstrated a downward trend in SC, reaching − 13.98 mm/per decade. TCPF changed in the same direction as that of TCPA. TCPA and TCPF were primarily concentrated in July–September and peaked in August. TCPA and TCPF and their contributions to total precipitation decreased from the southeast coast to the northwest inland. The maximum annual average TCPA and TCPF were 575.40 mm/annum and 19 days, respectively, in Hainan. Additionally, the contributions of TC to extreme precipitation far exceeded that to total precipitation. Our results provide a reference for water resource management and early warnings of water and drought disasters in China. [ABSTRACT FROM AUTHOR]

Purpose: Functionally graded material (FGM) is usually used in high temperature environment. Thick FGM spherical shells usually rarely consider the shear deformation effect of thickness. So the purpose of this study was to investigate the natural frequency directly from the homogeneous matrix under free vibration, in which elements contain the third-order shear deformation theory (TSDT) effect. Methods: This study was based on the formulations containing temperature-dependent FGM properties, nonlinear displacements, dynamic equations of motion and fully homogeneous equation. Thus the determinant of fully homogeneous coefficient matrix in sinusoidal oscillations can be used to calculate the numerical data of natural frequencies. Results: The numerical results of natural frequencies for SUS304/Si3N4 constituent materials were obtained. These results include the effects of stiffness integrals, c1 term, density integrals, temperature-dependent properties and power law index of FGMs on the vibrations of flexural, shear and twist modes. Some non-dimensional frequency parameters were also compared with published literature. Conclusions: Usually the values of dimensional first natural frequency are greater in value with c1=0 than that with c1=0.925925/mm2, including the TSDT effect, for a given meridional angle in thick FGM spherical shells. [ABSTRACT FROM AUTHOR]

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The crack initiation stress threshold is widely used in excavation industries as rock spalling strength when designing deep underground structures to avoid unwanted brittle failures. While various strain-based methods have been developed for the estimation of this critical design parameter, such methods are destructive and often requires subjective interpretations of the stress–strain curves, particularly in rocks with pre-existing microcracks or high porosity. This study explore the applicability of non-destructive ultrasonic through-transmission methods for determining rock damage levels by assessing the changes in transmitted signal characteristics during loading. The change in velocity, amplitude, dominant frequency, and root-mean-square voltage are investigated with four different rock types including marble, sandstone, granite, and basalt under various stress levels. Results suggest the rate of signal variations can be reliably used to estimate crack closure and crack initiation stress levels across the tested rocks before failure. Comparison of the results between the conventional techniques and the new proposed methods based on ultrasonic monitoring are further discussed. [ABSTRACT FROM AUTHOR]

Ultrasound assisted thawing (UAT) is an emerging thawing method in recent years, which can shorten thawing time and improve product quality. However, the application of UAT in aquatic products is less and there is no systematic study on the effect of frequency and power. The effect of frequency, used alone or in combination; combined with different power (180 or 220 W) during ultrasound assisted thawing on the thawing time, water-holding capacity (WHC), quality, and myofibrillar protein (MP) structure of sea bass (Lateolabrax maculatus) were evaluated in this experiment. UAT was found to improve the quality of thawed sea bass. Compared to flowing water thawing (FWT), UAT resulted in a lower thawing time. Samples treated with multi-frequency UAT (MUAT) at 180 W (MUAT-180-20/28/40) had a lower thawing time (44.92 min), higher hardness, higher chewiness, lower thiobarbituric acid reactive substances (TBARS) value, and more stable tertiary structure of MP compared with the single-frequency UAT (SUAT) and dual-frequency UAT (DUAT) treated samples. At the same time, MUAT at 220 W (MUAT-220-20/28/40) had a lower thawing time (47.50 min), a more suitable pH value, and lower total volatile basic nitrogen (TVB-N) value. In addition, DUAT at 220 W at 20 and 28 kHz (DUAT-220-20/28) had higher WHC, more stable sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and lower TBARS value. In consequence, UAT can improve the quality of thawed sea bass, especially at specific power and frequency, and better quality can be obtained, which can be studied in depth in the future. [ABSTRACT FROM AUTHOR]

The response of rock to dynamic loading is critical to the stability of underground engineering. This study experimentally investigated the mechanical responses of sandstone exposed to incremental and decremental frequency under compressive cyclic loading. The impact of loading frequency on amplitude of strain variation between the upper and lower bounds of cyclic stresses are revealed. The result shows that a higher frequency can incur a larger-amplitude variation of axial and volumetric strains between two bounds of cyclic stresses. The inelastic axial and radial strain ratios (defined in text) both exhibit good performance in early warning of rock failure. The cyclic loading stage (CLS) with the lowest inelastic strain ratio can be defined as the critical phase. This also applies to the evolution of secant modulus, the CLS with the peak secant modulus is used as the point to emit warning signals. The phase shift between stress–strain is frequency-dependent, a lower frequency results in a larger phase-shift. The evolution of damping ratio and dissipated energy ratio are almost frequency independent and both decrease with the ongoing of cycle. [ABSTRACT FROM AUTHOR]

One of the most critical complications of blasting in open-pit mines is blast-induced damage such as back break, which affects various aspects of safety and economy. Recognizing the effective parameters and predicting the amount of blast-induced damage can lead to reduce and prevent it. Therefore, several studies have been conducted on the effects of various parameters such as discontinuities conditions, host environment, and rock physical and mechanical properties on blast-induced damage. However, the effects of parameters such as discontinuity orientation, delay time, and different blasting patterns have been less studied due to the complexity of their modeling. In the present study, the effects of the various delay times, the square and stagger blasting patterns, and discontinuity orientation on blast-induced damage are investigated using numerical modeling. Finally, to assess the capability of different behavioral models to numerically simulate the blast-induced damage zone (back break), the Cohesion Weakening Friction Strengthening (CWFS) models were implemented and compared with the perfect plastic model. The results showed that although the delay time reduces the damage and vibration, very high delay time values are not effective. Also, some vibration frequencies have very low amplitudes in models in which the delay is applied. A comparison of square and stagger patterns showed that the possibility of damage is higher in the stagger pattern, but the vibration is almost the same at the far-field from blasting. Comparing the back break extension of the Calamine mine with the results of the perfect plastic and the CWFS models shows that the CWFS model predicts relatively more accurate. [ABSTRACT FROM AUTHOR]

For flexible elements of drives characterized by a constant speed of longitudinal motion, we propose a method for the analytic investigation of vibrations caused by the action of a periodic system of impulsive perturbations. On the basis of this method, we obtain analytic relations for the description of the determining parameters of nonlinear vibrations in the analyzed class of systems for both nonresonance and resonance cases. It is shown that, in the resonance case, the value of the amplitude of transition through the resonance strongly depends on the speed of longitudinal motion of the flexible element. [ABSTRACT FROM AUTHOR]

Background: Snacking is a common diet behaviour which accounts for a large proportion of daily energy intake, making it a key determinant of diet quality. However, the relationship between snacking frequency, quality and timing with cardiometabolic health remains unclear. Design: Demography, diet, health (fasting and postprandial cardiometabolic blood and anthropometrics markers) and stool metagenomics data were assessed in the UK PREDICT 1 cohort (N = 1002) (NCT03479866). Snacks (foods or drinks consumed between main meals) were self-reported (weighed records) across 2–4 days. Average snacking frequency and quality [snack diet index (SDI)] were determined (N = 854 after exclusions). Associations between snacking frequency, quality and timing with cardiometabolic blood and anthropometric markers were assessed using regression models (adjusted for age, sex, BMI, education, physical activity level and main meal quality). Results: Participants were aged (mean, SD) 46.1 ± 11.9 years, had a mean BMI of 25.6 ± 4.88 kg/m2 and were predominantly female (73%). 95% of participants were snackers (≥ 1 snack/day; n = 813); mean daily snack intake was 2.28 snacks/day (24 ± 16% of daily calories; 203 ± 170 kcal); and 44% of participants were discordant for meal and snack quality. In snackers, overall snacking frequency and quantity of snack energy were not associated with cardiometabolic risk markers. However, lower snack quality (SDI range 1–11) was associated with higher blood markers, including elevated fasting triglycerides (TG (mmol/L) β; – 0.02, P = 0.02), postprandial TGs (6hiAUC (mmol/L.s); β; – 400, P = 0.01), fasting insulin (mIU/L) (β; – 0.15, P = 0.04), insulin resistance (HOMA-IR; β; – 0.04, P = 0.04) and hunger (scale 0–100) (β; – 0.52, P = 0.02) (P values non-significant after multiple testing adjustments). Late-evening snacking (≥ 9 pm; 31%) was associated with lower blood markers (HbA1c; 5.54 ± 0.42% vs 5.46 ± 0.28%, glucose 2hiAUC; 8212 ± 5559 vs 7321 ± 4928 mmol/L.s, P = 0.01 and TG 6hiAUC; 11,638 ± 8166 vs 9781 ± 6997 mmol/L.s, P = 0.01) compared to all other snacking times (HbA1c remained significant after multiple testing). Conclusion: Snack quality and timing of consumption are simple diet features which may be targeted to improve diet quality, with potential health benefits. Clinical trial registry number and website: NCT03479866, https://clinicaltrials.gov/ct2/show/NCT03479866?term=NCT03479866&draw=2&rank=1 [ABSTRACT FROM AUTHOR]

Proper temperature management in electrical devices greatly boosts their performance. Thus, to maintain electrical devices at their optimal efficiency, combined hardware/software solutions are utilized for their thermal management. Here, we present a cost-effective, environmentally benign, and easy-to-implement chemical etching method to fabricate heat sinks with nano-sized roughened surfaces that can be utilized for the thermal management of central process units (CPUs) in computers. The fabricated heat sink was connected to a CPU dual cores Intel Pentium G2020 running two different benchmark programs from SPEC CPU2006 at a constant frequency. Nano-roughened heat sink (NRHS) reduced the maximum CPU temperature by nearly 4–8 °C and improved the program execution by 26% compared to the conventional heat sink (CHS). Meanwhile, a 57% increase in CPU lifetime was estimated, on average (comparing NRHS with CHS), which was aligned with the results obtained from imaging with a thermal camera. The operating temperature of the CPU connected to CHS at 2.1 GHz was almost the same as the operating temperature of CPU connected to NRHS at 2.9 GHz which means nearly 40% improvement in the processing frequency without increasing the operating temperature. [ABSTRACT FROM AUTHOR]

Research into self-oscillatory processes in semiconductors and semiconductor structures makes it possible to formulate the physical mechanism of these unique phenomena and create solid-state generators and sensors of physical quantities with frequency-amplitude output. It was established that the excitation conditions and parameters of self-oscillations of the current were studied in more detail only in silicon doped with manganese and zinc atoms, as well as in semiconductor compounds CdSe, CdS, InGa and in some structures, while the boundary regions of existence of these current instabilities depending on external factors were not very accurately determined in other materials. This led to the lack of reproducible results and a discrepancy in the correlation between the electrical parameters of the material and the parameters of self-oscillations of the current (amplitude, frequency). In this regard, the results of comprehensive studies of self-oscillations of current in silicon doped with impurity atoms of manganese, zinc, sulfur, and selenium are presented. A physical mechanism of current self-oscillations is proposed, which is in good agreement with the known experimental results obtained. [ABSTRACT FROM AUTHOR]

The model of horizontal layered structure in elastic solids has a wide range of applications in our real-world scientific research. To explore the propagation characteristics of cylindrical Rayleigh waves in a horizontally layered structure, we decompose the displacement using the Helmholtz decomposition method in the cylindrical coordinate system in order to use potential functions to describe the displacement and stress of the medium. Following this, the paper employs the transfer matrix method to derive the dynamic equations of axisymmetric Rayleigh waves in a horizontally layered elastic solid. After that, the equations are solved to obtain the Rayleigh wave dispersion curves and displacement expressions with Bessel function under these conditions. Lastly, through the calculations of four representative numerical examples, this paper verifies the consistency of the algorithm in calculating cylindrical Rayleigh wave dispersion curves and its agreement with experimental measurements, while demonstrating the characteristics of cylindrical Rayleigh wave displacement. [ABSTRACT FROM AUTHOR]

Purpose: In bolted steel structures, the damage is mostly seen due to loss of prestress in the bolts. Studies say that the loosened bolts can be detected by examining the dynamic response of the structure. Methods: The study of dynamic response includes the extraction of natural frequencies, mode shapes and damping ratios using vibrational analysis techniques. previous studies were mostly concentrated on the single bolt lap joints. In this work, a staggered bolted lap joint having five bolts is investigated experimentally using impact hammer technique and numerical analysis is done using the Transient analysis in Ansys workbench. Time vs Acceleration data is collected from both the experimental and numerical analysis. The raw data acquired is postprocessed to extract the dynamic parameters using MATLAB. Results: Frequency Response plots were drawn as they were efficient having both the input and output response data. Further the derivative techniques namely percentage change in frequencies, Natural frequency-based damage index, Modal Assurance Criterion (MAC), Modal Strain Energy (MSE) and Modal curvature are examined. Conclusion: Suggesting MSE is the better technique for further quantification of the damage in this joint. The studies conducted clearly shown the presence of damage in the structure and this methodology will be useful for structural integrity assessment of large-scale truss types of bolted steel structures. [ABSTRACT FROM AUTHOR]

Background: Failure of the structure may be avoided if, the damage is noticed at an early stage and proper remedial work is performed. In this context, this paper presents a detection of structural damage in steel beams, which are major load carrying members in bridges and buildings. Method: In the present study, the Generalized Flexibility Energy Quotient Difference Index (χ) is determined at various locations of the beam by introducing the damage by means of a cut by 0.5 mm to 2.5 mm at an interval of 0.25 mm. In practice, it is very difficult to capture all the modes of vibration. Hence, the method followed uses the first mode of vibration only for quantifying the magnitude of damage and its location. The validation is done between numerical simulations and experimental works for the estimation of first frequency. The efficiency of the method is tested by inducing the damage very close to the support. In ANN, the depth of cut at various locations of the beam and χ is utilized in the input layer. Results: The predicted depth of cut or severity of damage from the output layer of ANN model is compared with the actual depth of cut induced in the beam. Finally, the polynomial equations are formulated for the damaged elements, which are the major contribution of the present study. These equations can be used as a ready reckoner to estimate the actual depth of cut in the beam. This approach is validated through a beam with fixed ends and two-span beam, and the results indicate that this method is very much beneficial in preventing the structural failure. [ABSTRACT FROM AUTHOR]

Motivation: The analysis of vibrations of an elastic beam is one of the persistently challenging problems in engineering and mathematics. The differential equation of vibrations of a beam under large deformation, or the typical vibrations of an elastica, is hard to approximate and solve with the formulation in Cartesian coordinates. Objective: The higher-order nonlinear vibrations and couplings of modes of beams are analyzed with a novel method for a better understanding of dynamic properties. Method: The extended Galerkin method is used to obtain the first- to third-order nonlinear vibration frequencies and mode shapes of a cantilever beam with the exact equation of a beam with larger deflection, and the differential equation is transformed to a nonlinear algebraic equation for an improved analysis and solutions with the aid of linear mode shape functions. Results: From a cantilever beam in nonlinear vibrations, the numerical solutions of frequencies and mode shapes show that the approximate solutions are accurate in comparison to the exact solutions for small amplitudes with other methods. Conclusions: The effectiveness of the extended Galerkin method in solving nonlinear vibration equations is further demonstrated with a novel procedure and known results. [ABSTRACT FROM AUTHOR]

The relevance of the study is determined by the fact that fluctuations of inertial masses are found everywhere. In the field of construction and use of aviation and rocket technology, this topic is of particular importance. Like a three-dimensional plane coordinate system in coordinate plane Z, a multidimensional system with axes turned relative to each other through angles can be considered. There is an arbitrary vector emanating from the origin 0, . It is proved that points , which are the coordinates of the end of vector in the coordinate system , are the vertices of a regular polygon. The shape and dimensions of the polygon are not related to the coordinates of vector , i.e., are unchanged. The center of a regular polygon in all cases coincides with the middle of vector . In the considered (idealized) case, the polygon, at the vertices of which there are oscillating loads of masses m, lies in the Z plane (multipiston mechanism). In the considered multidimensional planar monoreactive oscillator, free harmonic linear oscillations of loads can occur. In this case, only kinetic energy is involved in the energy exchange. There is no need for elastic elements. The oscillator has no fixed natural oscillation frequency. The frequency depends on the initial speeds and positions of the loads. A regular polygon performs a double rotation (around point 0 and around point r). At the same time, the loads carry out linear harmonic oscillations with amplitude . The use of a crank-slider or crank-and-rod mechanism will allow organizing the parallel movement of goods. [ABSTRACT FROM AUTHOR]

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting, different power supply modes, current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel, and the macrostructure of electroslag ingots was analyzed. The results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply mode. The effects of different power supply modes, such as low-frequency, direct current straight polarity (DCSP), and direct current reverse polarity (DCRP), on reducing the depth of the metal pool increase in that order. By reducing the remelting current strength in the same power supply mode, the depth of metal pool is reduced. When compared to the binary slag system of 70% CaF2+30% Al2O3, the ternary slag system of 60% CaF2+20% Al2O3+20% CaO is more effective in reducing the depth of the metal pool during remelting. Utilizing the 60% CaF2+20% Al2O3+20% CaO ternary slag system results in a shallower and flatter metal pool, with columnar crystal growth occurring closer to the axial crystal. This effect is observed for both low frequency and direct current (DC) power supply modes. [ABSTRACT FROM AUTHOR]

Membrane sweeping is considered a simple and effective method for initiating spontaneous onset of labor. Despite the widely accepted membrane sweeping use to prevent post-term birth, the optimal frequency has not been estimated. We aimed to assess the effectiveness and safety of twice-weekly versus once-weekly membrane sweeping in post-term pregnancy prevention. Four different databases were searched for available clinical trials from inception to October 2022. We selected randomized controlled trials (RCTs) that compared twice-weekly membrane sweeping in intervention group versus once-weekly membrane sweeping in control group among pregnant women with singleton pregnancy at ≥ 39 gestational weeks. Our primary outcomes were the rate of spontaneous onset of labor and the requirement for formal methods of labor induction. Our secondary outcomes were sweeping to delivery interval in days, gestational age at delivery in weeks, Bishop score at admission, chorioamnionitis, and premature rupture of membranes. Three RCTs (596 patients) were included. Twice-weekly membrane sweeping was associated with significant increase in the rate of spontaneous onset of labor and significant decline in labor induction rate in comparison with once-weekly group. Duration from sweeping to delivery was significantly shorter among the twice-weekly group (p<0.001). Furthermore, gestational age at delivery was significantly earlier in the twice-weekly group. A significantly higher Bishop score at admission was observed in the twice-weekly group (p=0.02). There were no significant differences across both groups in chorioamnionitis and premature rupture of membranes. In conclusion, twice-weekly membrane sweeping is more effective in preventing post-maturity pregnancy than once-weekly sweeping without added adverse events. [ABSTRACT FROM AUTHOR]

With a generally warming global climate, the number of Tetranychus truncatus specimens in the Hexi region in China has been increasing. As ectotherms, the growth and development of T. truncatus are greatly affected by changes in environmental temperature. The effect of heatwaves on organisms depends on a delicate balance between damage and repair periods. Therefore, we simulated nine patterns of periodically recurring changes in the frequency of high-temperature days using an intraday gradual temperature change model to study and compare the effects on the development and reproduction of pyridaben-sensitive and -resistant strains of T. truncatus. The results showed that the influence of the frequency of high-temperature days on developmental stages, longevity and fecundity was different between the two strains. The egg and immature stages of the sensitive strain were all affected by hot days, whereas the adult stage was less affected by the frequency. The egg stage of the resistant strain was less affected; it was mainly affected in the immature and adult stages. Under the moderate condition of increasing the proportion of days at normal temperature, the longevity of the resistant strain gradually increased and reached a maximum at a 1:3 frequency, and then it decreased with the increase in high-temperature days. The longevity of the sensitive strain was less affected by frequency, and there was no significant difference between most treatment and control groups. In addition, both sensitive and resistant strains were able to complete growth and development under all nine frequencies of high-temperature days, but the reproductive rate was lower than it was at normal temperatures, indicating that both strains of T. truncatus adapted to high temperatures at the expense of reduced reproduction rates. This lays a key theoretical foundation for predicting the occurrence of agricultural pest populations under the background of climate warming and developing appropriate control strategies. [ABSTRACT FROM AUTHOR]