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Microfluidics are crucial for managing small-volume analytical solutions for various applications, such as disease diagnostics, drug efficacy testing, chemical analysis, and water quality monitoring. The precise control of flow control devices can generate diverse flow patterns using pneumatic control with solenoid valves and a microcontroller. This system enables the active modulation of the pneumatic pressure through Arduino programming of the solenoid valves connected to the pressure source. Additionally, the incorporation of solenoid valve sets allows for multichannel control, enabling simultaneous creation and manipulation of various microflows at a low cost. The proposed microfluidic flow controller facilitates accurate flow regulation, especially through periodic flow modulation beneficial for droplet generation and continuous production of microdroplets of different sizes. Overall, we expect the proposed microfluidic flow controller to drive innovative advancements in technology and medicine owing to its engineering precision and versatility. [ABSTRACT FROM AUTHOR]

Physical interaction with patients, for example conducted as part of a diagnostic examination or surgical procedure, provides clinicians with a wealth of information about their condition. Simulating this interaction is of great interest to researchers in both haptics and medical education, and the development of softness changing tactile interfaces is important in recreating the feel of different soft tissues. This paper presents designs for a variety of novel electromechanical and electromagnetic mechanisms for controlling particle jamming-based, hardness changing tactile displays, intended to allow medical trainees to experience these physical interactions in a range of simulation settings such as clinical skills teaching laboratories. Each design is then subjected to a battery of mechanical tests to evaluate its effectiveness compared to the state of the art, as well as their suitability for simulating the physical hardness of different types of soft tissues, previously characterised in established literature. These results demonstrate that all of the technologies presented are able to exhibit a measurable hardness change, with Shore hardness values between 3A and 57A achieved by the most effective constriction-based device. The electromechanical devices based on constriction and compression, and the state-of-the-art pneumatic device, were able to achieve hardness changes within a range that is useful for replicating the softness of organic tissue. The electromechanical and electromagnetic devices were also found to effect their full range of hardness change in less than a second, compared to several seconds for the state-of-the-art. These results show that the performance of softness changing tactile displays can be improved with the electromechanical actuation techniques proposed in this paper, and that such displays are able to replicate the physical characteristics of soft tissues and may therefore be of benefit in medical training and simulation scenarios. [ABSTRACT FROM AUTHOR]

This review aimed to determine the effectiveness of Intermittent Pneumatic Compression (IPC) intervention on Deep Vein Thrombosis (DVT) in surgical patients. An electronic database search was conducted with PubMed, OVID-MEDLINE, EMBASE, and CENTRAL, from September 22 to 28, 2023. Three researchers independently selected the studies, assessed their methodological quality, and extracted relevant data. We conducted a meta-analysis of the effect of IPC versus the control group and summarized the intervention results from the included studies. Of the 2,696 articles identified 16 randomized control trials met the inclusion criteria for review. IPC interventions significantly affected DVT prevention (OR = 0.81, 95% CI: 0.59–1.11). In the subgroup analysis, there was a significant pooled effect (OR = 0.41, 95% CI: 0.26–0.65]), when the comparison group was no prophylaxis group. However, when the comparison groups were the pharmacologic prophylaxis group ([OR = 1.32, 95% CI 0.78–2.21]) and IPC combined with the pharmacologic prophylaxis group (OR = 2.43, 95% CI: 0.99–5.96) did not affect DVT prevention. The pooled effects of Pulmonary Embolism (PE) (OR = 5.81, 95% CI: 1.25–26.91) were significant. IPC intervention showed a significant effect on bleeding prevention (OR = 0.17, 95% CI: 0.08–0.36) when compared to IPC combined with the pharmacologic groups. IPC intervention effectively prevented DVT, PE, and bleeding in surgical patients. Therefore, we propose that IPC intervention be applied to surgical patients to avoid DVT, pulmonary embolism, and bleeding in the surgical nursing field as scientific evidence suggests. [ABSTRACT FROM AUTHOR]

Winter oilseed rape (Brassica napus L.), Europe's foremost oilseed crop, is significantly impacted by hailstorms, leading to substantial yield reductions that are difficult to predict and measure using conventional methods. This research aimed to assess the effectiveness of photosynthetic efficiency analysis for predicting yield loss in winter rapeseed subjected to hail exposure. The aim was to pinpoint the chlorophyll fluorescence parameters most affected by hail stress and identify those that could act as non-invasive biomarkers of yield loss. The study was conducted in partially controlled conditions (greenhouse). Stress was induced in the plants by firing plastic balls with a 6 mm diameter at them using a pneumatic device, which launched the projectiles at speeds of several tens of meters per second. Measurements of both continuous-excitation and pulse-modulated-amplitude chlorophyll fluorescence were engaged to highlight the sensitivity of the induction curve and related parameters to hail stress. Our research uncovered that some parameters such as Fs, Fm', ΦPSII, ETR, Fo, Fv/Fm, and Fv/Fo measured eight days after the application of stress had a strong correlation with final yield, thus laying the groundwork for the creation of new practical protocols in agriculture and the insurance industry to accurately forecast damage to rapeseed crops due to hail stress. [ABSTRACT FROM AUTHOR]

• metronomic rolls for player piano have so far been commonly considered devoid of scientific interest as mere mechanical transpositions of the musical score. • instead, they can be considered valuable witnesses of the executive practice of the early twentieth century. • through a software based on peaks detection applied to the ordered vector of detected Inter Onset Intervals (IOIs) it was possible to identify numerous examples of expressive passages, therefore deviations from the score. • this indicates that computational information retrieval applied to MIDI or audio rendered from the rolls can bring new scientifically significant knowledge. • the techniques used here could be applied directly or adapted to obtain useful information also not related to expressiveness. Between the last years of the nineteenth century and the first two decades of the twentieth century, the production and use of rolls for player piano became widespread. These were strips of perforated paper wrapped around a cylinder, capable of activating in the instrument a pneumatic mechanism for the automatic operation of the piano keys. The metronomic-type rolls were produced manually, by transposing the piece's score into the paper's perforation. In this contribution, we propose a solution based on the automatic identification of peaks in the distribution of the Inter-Onset-Intervals (IOIs) of the notes for the detection, within metronomic rolls, of timing-related expressive areas, i.e. of musical passages in which deviations in the length of the holes with respect to what is prescribed in the score are operated intentionally to add expressiveness. The identified algorithm, applied to a dataset of approximately 700 rolls converted into MIDI format, showed good sensitivity, and made it possible to identify in a relatively short time numerous examples of intentional expressiveness in the analyzed repertoire, commonly and erroneously considered a mere mechanical transposition of the score. In the conclusions, some reflections on the relevance of this research in the musicological field are proposed. [ABSTRACT FROM AUTHOR]

The pneumatic centralized fertilizer discharge system is an important part of pneumatic fertilization machinery and mainly includes a fertilizer discharge device, an air–fertilizer mixing device and a pneumatic distribution device. In this paper, the mechanical structure, key parameters and research methods of pneumatic centralized discharge devices, air–fertilizer mixing devices and pneumatic distribution devices at home and abroad are briefly analyzed. The advantages and disadvantages of these existing devices are summarized, the existing problems are discussed and improvement methods are put forward. In this paper, the structural adaptability, uniformity and stability of the fertilizer discharge of different types of fertilizer discharge devices, such as external groove wheel types, spiral types and centrifugal types, are comprehensively analyzed. The working principle of air–fertilizer mixing devices using the Venturi effect to achieve the uniform mixing of fertilizer and airflow is expounded. The effects of air–fertilizer mixing devices with different structural forms and parameters on mixing performance and the motion characteristics of air–solid two-phase flows are analyzed. The influence of the internal structure, key parameters and distribution mode of pneumatic distribution devices on the uniformity and accuracy of fertilizer distribution are analyzed. This paper focuses on how to improve the uniformity, stability and consistency of discharge across rows provided by the pneumatic centralized fertilizer discharge system. The research status and progress made regarding the core components of the pneumatic centralized fertilizer discharge system at home and abroad are summarized. Based on different research results, the key factors and methods for improving the uniformity of fertilizer discharge are discussed. [ABSTRACT FROM AUTHOR]

Wearable mechatronics for powered orthoses, exoskeletons and prostheses require improved soft actuation systems acting as 'artificial muscles' that are capable of large strains, high stresses, fast response and self-sensing and that show electrically safe operation, low specific weight and large compliance. Among the diversity of soft actuation technologies under investigation, pneumatic devices have been the focus, during the last couple of decades, of renewed interest as an intrinsically soft artificial muscle technology, due to technological advances stimulated by applications in soft robotics. As of today, quite a few solutions are available to endow a pneumatic soft device with linear actuation and self-sensing ability, while also easily achieving these features with off-the-shelf materials and low-cost fabrication processes. Here, we describe a simple process to make self-sensing pneumatic actuators, which may be used as 'inverse artificial muscles', as, upon pressurisation, they elongate instead of contracting. They are made of an elastomeric tube surrounded by a plastic coil, which constrains radial expansions. As a novelty relative to the state of the art, the self-sensing ability was obtained with a piezoresistive stretch sensor shaped as a conductive elastomeric body along the tube's central axis. Moreover, we detail, also by means of video clips, a step-by-step manufacturing process, which uses off-the-shelf materials and simple procedures, so as to facilitate reproducibility. [ABSTRACT FROM AUTHOR]

Rerounding is a technique for remediating excess deflection in thermoplastic pipe. A pneumatic device vibrates along the vertical axis and pushes against the inside crown and invert to restore the original pipe shape and redistribute the surrounding backfill. A systematic evaluation of the method was justified because rerounding is routinely used by contractors to remediate deflected thermoplastic pipes, and it has not been investigated outside of a few previous reports. Three 900-mm and two 450-mm corrugated high-density polyethylene (HDPE) pipes were installed in various bedding and backfill materials. Test pipes were intentionally installed with substantial deflection (10% or more) and then rerounded. The pipe conditions were measured and monitored by collecting profiles, measuring vertical deflections, and monitoring soil pressure, soil stiffness, backfill characteristics, and pipe corrugation depth before and after rerounding. The data from the deflection, soil stiffness, corrugation, and soil pressure monitoring confirmed the following: (1) during rerounding, soil particles migrated and soil pressure was redistributed; fine material from the crown and springline moved down toward the haunch area, at least in the well-graded aggregate backfill; (2) it is difficult to successfully reduce deflection in corrugated HDPE pipes in well-graded aggregate backfill; (3) installing the pipes with excess deflection proved a significant challenge, as all the pipes required much effort to reach sufficient deflection. It proved necessary to create a device to hold the pipe in a deflected state during backfilling; (4) rerounding successfully reduces deflections for pipes in sand backfill; and (5) test pipes backfilled with Ohio Department of Transportation (ODOT) Type-3 backfill were easy to reround, but a change in environmental conditions and/or dynamic loading may create a change in the stress path leading to excessive deflection and reversal of the effects of rerounding. [ABSTRACT FROM AUTHOR]

A miniature pneumatic bellows device was designed for in-situ testing inside the scanning electron microscope. The device uses a pneumatic actuator to load the specimen and displacement is directly monitored with a linear variable differential transformer sensor. Its application allowed the direct monitoring of microstructural and defect evolution in materials at the micro scale. The data produced by this testing device, in combination with measurements from micro digital image correlation, were successfully used to model the crystal plasticity of a martensitic/bainitic steel at the microstructural length scale. [ABSTRACT FROM AUTHOR]

Unconventional machining methods include electrochemical micromachining (EMM). EMM is suitable for hard and difficult-to-cut materials used in the manufacture of special forms of machine parts used in aeronautics and hydro pneumatic machinery. As a result of a set of electrical, mechanical and chemical parameters, the EMM process is a very complex process. The analytical modeling of the method is therefore difficult. The artificial neural network (ANN) significantly simplifies the relationship between input and output parameters due to the large number of measurements required. With a set of data containing very different machining parameter choices, the neural network was trained. This paper presents the results obtained for predicting certain output parameters. The ANN is used in this paper to determine the model for parameter optimization. To represent the relationship between machining rate (MR), overcut (OC) and input parameters, an ANN model has been established that adapts the Levenberg-Marquardt algorithm and Bayesian regularization (LMABR). The model is shown to be efficient, and optimized machining parameter improves the MR and OC. [ABSTRACT FROM AUTHOR]

Multisensory human–machine interfaces for virtual- or augmented-reality systems are lacking wearable actuated devices that can provide users with tactile feedback on the softness of virtual objects. They are needed for a variety of uses, such as medical simulators, tele-operation systems and tele-presence environments. Such interfaces require actuators that can generate proper tactile feedback, by stimulating the fingertips via quasi-static (non-vibratory) forces, delivered through a deformable surface, so as to control both the contact area and the indentation depth. The actuators should combine a compact and lightweight structure with ease and safety of use, as well as low costs. Among the few actuation technologies that can comply with such requirements, pneumatic driving appears to be one of the most promising. Here, we present an investigation on a new type of pneumatic wearable tactile displays of softness, recently described by our group, which consist of small inflatable chambers arranged at the fingertips. In order to objectively assess the perceptual response that they can elicit, a systematic electroencephalographic study was conducted on ten healthy subjects. Somatosensory evoked potentials (SEPs) were recorded from eight sites above the somatosensory cortex (Fc2, Fc4, C2 and C4, and Fc1, Fc3, C1 and C3), in response to nine conditions of tactile stimulation delivered by the displays: stimulation of either only the thumb, the thumb and index finger simultaneously, or the thumb, index and middle finger simultaneously, each repeated at tactile pressures of 10, 20 and 30 kPa. An analysis of the latency and amplitude of the six components of SEP signals that typically characterise tactile sensing (P50, N100, P200, N300, P300 and N450) showed that this wearable pneumatic device is able to elicit predictable perceptual responses, consistent with the stimulation conditions. This proved that the device is capable of adequate actuation performance, which enables adequate tactile perceptual performance. Moreover, this shows that SEPs may effectively be used with this technology in the future, to assess variable perceptual experiences (especially with combinations of visual and tactile stimuli), in objective terms, complementing subjective information gathered from psychophysical tests. [ABSTRACT FROM AUTHOR]

The small size, light weight, irregular shape, and impurities that characterize seed groups increase clogging tendencies in the traditional seed-metering device thereby making it difficult to achieve high-speed precision seeding. A pneumatic seed-metering device with good seed-filling performance for carrot was designed in this study. By analyzing the movement state of seeds in the device under the theoretical condition, it was concluded that the minimum critical negative pressure value of air chamber was 0.32 kPa, which provided a theoretical basis for simulation and testing. ANSYS 17.0 Software was used to simulate the shape of the seeding plate hole. By comparing the pressure, air flow stability between the suction surface and the plug removal surface of the convection field, it was concluded that the conical hole was optimal. A bench verification test was conducted on the device. The average qualified rate, missing rate, and replaying rate were 81.48%, 4.07%, and 14.45%, respectively, which provided a strong reference for the design of carrot precision seed-metering device. [ABSTRACT FROM AUTHOR]

Background: In neurosurgical patients, the risk of developing venous thromboembolism (VTE) is high due to the relatively long duration of surgical interventions, usually long immobilization time after surgery, and possible neurological deficits which can negatively influence mobility. In neurosurgical clinical practice, there is lack of consensus on optimal prophylaxis against VTE, mechanical or pharmacological. Objective: To systematically review available literature on the incidence of VTE in neurosurgical interventions and to establish an optimum prevention strategy. Methods: A literature search was performed in PubMed, Embase, Web of Science, Cochrane Library, and EmCare, based on a sensitive search string combination. Studies were selected by predefined selection criteria, and risk of bias was assessed by Newcastle–Ottawa Quality Assessment Scale and Cochrane risk of bias. Results: Twenty-five studies were included, half of which had low risk of bias (21 case series, 3 comparative studies, 1 RCT). VTE was substantially higher if the evaluation was done by duplex ultrasound (DUS), or another systematic screening method, in comparison to clinical evaluation (clin). Without prophylaxis DVT, incidence varied from 4 (clin) to 10% (DUS), studies providing low molecular weight heparin (LMWH) reported an incidence of 2 (clin) to 31% (DUS), providing LMWH and compression stockings (CS) reported an incidence of 6.4% (clin) to 29.8% (DUS), and providing LMWH and intermittent pneumatic compression devices (IPC) reported an incidence of 3 (clin) to 22.3% (DUS). Due to a lack of data, VTE incidence could not meaningfully be compared between patients with intracranial and spine surgery. The reported incidence of pulmonary embolism (PE) was 0 to 7.9%. Conclusion: Low molecular weight heparin, compression stockings, and intermittent pneumatic compression devices were all evaluated to give reduction in VTE, but data were too widely varying to establish an optimum prevention strategy. Systematic screening for DVT reveals much higher incidence percentages in comparison to screening solely on clinical grounds and is recommended in follow-up of neurosurgical procedures with an increased risk for DVT development in order to prevent occurrence of PE. [ABSTRACT FROM AUTHOR]

The development of microfluidic systems for biological assays presents challenges, particularly in adapting traditional optical absorbance assays to smaller volumes or to microfluidic formats. This often requires assay modification or translation to a fluorescence version, which can be impractical. To address this issue, our group has developed the μChopper device, which uses microfluidic droplet formation as a surrogate for an optical beam chopper, allowing for lock-in analysis and improved limits of detection with both absorbance and fluorescence optics without modifying the optical path length. Here, we have adapted the μChopper to low-cost optics using a light-emitting diode (LED) source and photodiode detector, and we have fabricated the pnuematically valved devices entirely by 3D printing instead of traditional photolithography. Using a hybrid device structure, fluidic channels were made in polydimethylsiloxane (PDMS) by moulding onto a 3D-printed master then bonding to a prefabricated thin layer, and the pneumatic layer was directly made of 3D-printed resin. This hybrid structure allowed an optical slit to be fabricated directly under fluidic channels, with the LED interfaced closely above the channel. Vacuum-operated, normally closed valves provided precise temporal control of droplet formation from 0.6 to 2.0 Hz. The system was validated against the standard plate reader format using a colorimetric fructosamine assay and by quantifying fructosamine in human serum from normal and diabetic patients, where strong correlation was shown. Showing a standard benefit of microfluidics in analysis, the device required 6.4-fold less serum volume for each assay. This μChopper device and lower cost optical system should be applicable to various absorbance based assays in low volumes, and the reliance on inexpensive 3D printers makes it more accessible to users without cleanroom facilities. [ABSTRACT FROM AUTHOR]

Introduction: The treatment of venous leg ulcers (VLUs) is a difficult medical problem both for patients and health providers. Objectives: The aim of study was to evaluate the therapeutic efficacy of intermittent pneumatic compression device and shortstretch bandaging in the treatment of VLUs. Material and methods: In this study, 26 patients with venous leg ulcers were included: 18 males (69%) and eight females (31%), at the mean age of 65.0±9.7 (min: 47, max: 80) years. Patients in group I had superficial venous insufficiency, but in group II -- superficial and deep venous insufficiency. All patients underwent intermittent pneumatic compression (IPC) therapy for 15 days and next, double-layer, short-stretch bandaging for 15 days. The progress in wound healing was evaluated via the Photographic Wound Assessment Tool (PWAT) and Wound Bed Score (WBS). Results: In both groups of patients, statistically significant changes in the WBS and PWAT value point scales were observed: in group I, by an average of 4.7±5.0 points, and in group II, by an average of 6.1±4.5 points on the WBS scale, and in group I, by an average of 4.3±4.2 points, and in group II, by an average of 3.7±3.3 points on the PWAT scale. Conclusions: In the present trial, it has been shown that IPC (60 mm Hg) applied 60 minutes a day, 7 times a week; and bandages (40 mm Hg) applied 10-12 hours a day, are effective in treating both superficial and deep VLUs. [ABSTRACT FROM AUTHOR]

This study proposes a negative-pressure fruit-soil separating device for peanuts cultivated in hilly and mountainous areas after combined harvesting, and the mechanism of the movement of the material in the process of material screening, fruit-soil separating, and pneumatic conveying of the device was analyzed. In addition, a four-factor, three-level Box-Behnken regression design test was used to explore the optimum operating parameters of the peanut fruit-soil separation device. The results showed that the best fruit-soil separation effect was achieved when the wind speed of the blower was 13.58 m/s, the height of the suction nozzle from the screen surface was 27 mm, the length of the suction port was 64 mm, and the feeding rate was 600 kg/h. Validation tests demonstrated that the impurity rate of 0.16% and the peanut pod loss rate of 0.2% exceeded the industry standard, indicating superior performance. [ABSTRACT FROM AUTHOR]

Summary: Horses with enterolithiasis may develop clinical signs of colic due to partial or complete obstruction of the right dorsal, transverse or small colon. Laparotomy followed by enterotomy at the site of obstruction or mobilisation of enteroliths to intestinal segments deemed more appropriate for incision is indicated in these cases. However, surgical removal of enteroliths lodged in nonexteriorisable intestinal segments and/or not amenable to mobilisation may be labour intensive and dangerous. Pneumatic impact (or ballistic) lithotripsy is a potential tool for surgical resolution of simple and complex cases of enterolithiasis in horses. This study describes the use of a pneumatic lithotripsy device for intraluminal enterolith fragmentation in five cases of enterolithiasis. Seven calculi were successfully fragmented. In four cases, fragmentation was achieved at the site of obstruction and fragments exteriorised through an enterotomy incision created for device introduction or advanced towards the rectum and removed. In two cases, enteroliths were manipulated back to the pelvic flexure, fragmented and removed. Findings of this study suggest that intraluminal enterolith fragmentation can be used to avoid long enterotomy incisions and facilitate removal of calculi lodged in bowel segments that cannot be exteriorised. However, it is important to be aware of the risks of enterolith fragmentation in nonexternalisable bowel segments that cannot be visualised for intestinal viability assessment. [ABSTRACT FROM AUTHOR]

A haptic device provides users with physical feedback to enhance their experience in virtual reality (VR). We developed a multimodal haptic suit, called as Pneumatic and Acoustic (PA) suit, which exhibits high-resolution haptic feedback, and applies high pressure and realistic vibration to a user. The PA suit artificially simulates the sensation of brief and strong collisions such as the impact of an explosion, ball, or fist. The pneumatic actuators, consisting of 40 air bladders, are designed as bellows-type pneumatic devices for vertical inflation. The air bladders are placed on the chest at an equal interval distance of 30 mm for high-resolution feedback. The acoustic actuators use an effective sound signal of a collision similar to realistic vibrations. This study aims to examine the effectiveness of our multimodal haptic suit in improving VR experience of users. The recognition tests clearly show that participants distinguish between the haptic patterns and position of collided virtual objects with the suit. The user study involving a collision of a ball shows that the PA suit transmits the approximate pressure of a real ball collision with artificial haptic feedback. Our receiving ball and explosion VR simulations confirm that the PA suit improves a VR experience depending on the types of actuators and VR contents. The results prove that the PA suit creates distinguishable haptic patterns for guiding a task and improves the VR experience of users with powerful and multimodal haptic feedback hence providing high-quality VR simulation. [ABSTRACT FROM AUTHOR]

Postal services are often considered by the different institutions as a back-up service. Taking into account that in case of large geographical coverage these services can generate significant costs, it is important to optimize the postal service functions within these institutions and to develop the already existing conventional postal services. Within the frame of this article the authors review the logistics processes of the postal services at the University of Miskolc to propose improvements to these processes focusing on delivery. The main regulatory elements and the logistics processes of the institutional postal services are discussed and some critical remarks are described focusing on three main areas: the facility location optimization of the institutional postal services, the lack of use of modern technologies and the lack of modern administrative facilities. On the basis of these criticisms, the authors define recommendations for improving institutional postal services. Regarding the facility location optimization problem, a mathematical model and an optimization algorithm is described to evaluate the efficiency of the logistics processes of delivery services. The proposed methodology supports a cost-based analysis of different solution variants and a prioritybased differentiation between institutions and offices. The suggested approach is tested with a real scenario, where the numerical results validate the efficiency of the evaluation of optimization algorithm. The second improvement direction is the application of a pneumatic tube system. The authors show the most important parts of the proposed pneumatic tube system, which can lead to decreased labor cost and increased service level. [ABSTRACT FROM AUTHOR]

Objective. To search, evaluate, and summarize the best evidence of intermittent pneumatic compression devices to prevent venous thromboembolism in trauma patients. Method. Evidence retrieval was conducted from top to bottom according to the "6S" evidence model, including guidelines, clinical decision making, evidence summary, expert consensus, and systematic reviews. The retrieval time limit was from the establishment of the database to August 31, 2022. Two researchers independently evaluated the quality of the literature, extracted evidence, and summarized evidence. Results. A total of 140 studies were obtained in the literature retrieval, and 50 studies were obtained after rechecking and reading the title and abstract. After combining the inclusion and exclusion criteria, 19 studies were finally included. Among them, there were 12 guidelines, 1 clinical decision making, 1 evidence summary, 1 expert consensus, and 4 systematic reviews. The 27 best pieces of evidence were summarized from the four dimensions of pretreatment evaluation, contraindications and applicable conditions, treatment strategies, training, and patient education. Conclusion. This study summarized the evidence of using an intermittent pneumatic compression device to prevent venous thromboembolism in trauma patients and provided the basis for scientific and effective standardized management of mechanical thromboembolism prevention. When applying evidence, it is necessary to combine clinical practice and patient wishes and select evidence pertinent to improving the effectiveness of intermittent pneumatic compression devices in preventing venous thromboembolism. In addition, compliance with the clinical application of IPC is relatively low, so we should start from two aspects before the application of evidence. We should not only increase the number of IPCs but also strengthen the training of VTE prevention knowledge and practical skills of medical staff to provide good health education for patients and their families to improve compliance with the clinical application of IPC. [ABSTRACT FROM AUTHOR]

To improve the harvesting efficiency of the sphere fruits and reduce the workload of post-harvest classification, an air-suction sphere fruit classifier was designed in this paper, which can achieve the separation of high-quality fruit and common fruit through a pneumatic device according to the size and quality of the fruit when the cones are picked. First, three fruit pickers with various shapes are proposed, and the characteristics of the external flow field are analyzed, and a fruit picker that can maximize the classification efficiency is obtained. Then, the internal flow field of the classification pipeline was analyzed, the pressure and velocity changes in the classification pipeline were studied, and the displacement changes and classification of high-quality and common fruits in the classification pipeline were analyzed by particle simulation. According to the three influencing factors of pressure divider tube inner diameter, inclination angle, and outlet volume flow rate, an orthogonal test is designed, and the regression equation of fruit classification accuracy is fitted by the Box-Behnken method. The optimal factor parameters are obtained through response surface optimization: pressure divider tube inner diameter D3 = 48 mm, inclination angle = 60°, outlet volume flow = 0.01 m3/s. Research content provides a basis for the application of gas–solid separation technology in fruit classification. [ABSTRACT FROM AUTHOR]

Recently, the number of older people and the reduction in infant birth rates in Japan have increased. Elderly against the younger increased to more than 28.9% in 2020. According to the Japanese aging society, a welfare pneumatic device to rehabilitate the temporally injured elderly and the disabled has been actively researched and developed. However, the developed rehabilitation device is almost always used for a patient who is not bedridden. Therefore, the joint of a bedridden patient is given only a passive exercise, by a physical therapist (PT). In this study, in order to reduce the burden of PTs, we aim to develop a rehabilitation device that can be used by anyone assisting the bedridden patient. The target joint was decided to be an ankle-joint because it is difficult for patients with contractions to walk. Therefore, a fan-shaped pneumatic soft actuator (FPSA) using a no-stretch hose with weaved bellows and silicone rubber string was proposed and tested. In addition, the characteristics of FPSA with different pitches and lengths are measured. To predict the bending angle of FPSA, a simplified shape analytical model of it is proposed. It can be confirmed that a calculated bending angle of FPSA using the model generally agrees with the experimental result. The proposed analytical model is a first-stage model that does not include the influence of external forces on FPSA. The ankle-joint rehabilitation device using FPSAs is proposed and tested, where an ankle-joint is changed from a plantarflexion to a dorsiflexion motion by pressurizing both FPSAs on the tested device. And it can be confirmed that a range of motion ("ROM" for short) is satisfied in an inversion and eversion driven by operating one or another FPSA on the device. [ABSTRACT FROM AUTHOR]

Existing approaches to robotic manipulation often rely on external mechanical devices, such as hydraulic and pneumatic devices or grippers. Both types of devices can be adapted to microrobots only with difficulties and for nanorobots not all. Here, we present a fundamentally different approach that is based on tuning the acting surface forces themselves rather than applying external forces by grippers. Tuning of forces is achieved by the electrochemical control of an electrode's diffuse layer. Such electrochemical grippers can be integrated directly into an atomic force microscope, allowing for 'pick and place' procedures typically used in macroscopic robotics. Due to the low potentials involved, small autonomous robots could as well be equipped with these electrochemical grippers that will be particularly useful in soft robotics as well as nanorobotics. Moreover, these grippers have no moving parts and can be incorporated in new concepts for actuators. The concept can easily be scaled down and applied to a wide range of objects, such as colloids, proteins, and macromolecules. [ABSTRACT FROM AUTHOR]

Objectives: This study was carried out to investigate a new device for axial loading MRI (alMRI) in the diagnosis of lumbar spinal stenosis (LSS). Methods: A total of 87 patients with suspected LSS sequentially underwent conventional MRI and alMRI using a new device with pneumatic shoulder-hip compression mode. Four quantitative parameters of dural sac cross-sectional area (DSCA), sagittal vertebral canal diameter (SVCD), disc height (DH), and ligamentum flavum thickness (LFT) at L3-4, L4-5, and L5-S1 in both examinations were measured and compared. Eight qualitative indicators were compared as valuable diagnostic information. Image quality, examinee comfort, test–retest repeatability, and observer reliability were also assessed. Results: Using the new device, all 87 patients successfully completed alMRI with no statistically significant differences in image quality and examinee comfort from conventional MRI. Statistically significant changes were observed in DSCA, SVCD, DH, and LFT after loading (p < 0.01). SVCD, DH, LFT, and DSCA changes were all positively correlated (r = 0.80, 0.72, 0.37, p < 0.01). Eight qualitative indicators increased from 501 to 669 after axial loading, for a total increase of 168 (33.5%). Nineteen patients (21.8%, 19/87) developed absolute stenosis after axial loading and 10 of them (11.5%, 10/87) also had a significant reduction in DSCA (> 15 mm2). The test–retest repeatability and observer reliability were good to excellent. Conclusion: The new device is stable for performing alMRI and can exacerbate the severity of spinal stenosis, providing more valuable information for diagnosing LSS and reducing missed diagnoses. Key Points: • The new axial loading MRI (alMRI) device could detect a higher frequency of patients with lumbar spinal stenosis (LSS). • The new device with pneumatic shoulder-hip compression mode was used to investigate its applicability in alMRI and diagnostic value for LSS. • The new device is stable for performing alMRI and can provide more valuable information for diagnosing LSS. [ABSTRACT FROM AUTHOR]

Satellite telemetry is critical for collecting fine-scale temporal and spatial data on individual animals that has broad-scale applicability at population and species levels. There have been significant advances in the remote deployment of satellite telemetry devices on large cetacean species. However, the development of comparable remote attachment methodologies for small cetaceans is still limited. Currently, satellite tag attachment for small cetaceans requires manual capture that increases the risk to the target animal, can be logistically challenging, and cost prohibitive. The goal of this project was to develop a novel tool to remotely attach single-pin satellite telemetry devices to the dorsal fin of individual small cetaceans. Three different spring-loaded designs and one pneumatic version of the remote attachment device were built in an iterative process to identify a successful deployment methodology. Ultimately, as a result of logistical challenges associated with a Category 5 hurricane, the COVID-19 pandemic, and engineering complexities related to dorsal fin morphology and small cetacean behavior, the objective of this project was not met. However, lessons learned from these attempts to develop this new sampling tool have applicability for future researchers in the successful completion of a safe and effective methodology for remote attachment of satellite tags to small cetacean dorsal fins. [ABSTRACT FROM AUTHOR]

Increasing the efficiency of machines and equipment used not only in metallurgy, but also in other industries requires using modern scientific and technological ideas and developments to create and improve machines. Repair operations in metallurgy include break-up of refractory lining as one of the most labor-intensive operations. To mechanize this operation, hydraulic excavators equipped with a hammer are successfully used. Hydraulic hammers are more effective than pneumatic devices in breaking up very hard structures, including concrete foundations, monolithic slag, metallized conglomerates. One of the options for improving the energy efficiency of the demolition of hard structures in metallurgy is the rational use of the impact energy of hydraulic hammers. This problem can be solved by using the effect of the geometrical parameters of the striking parts of a machine on the impact efficiency of the tool. The essence of the approach is to generate a shock pulse shaped so as to follow the demolition stages. This requires a variable destroying load, which cannot be ensured by conventional hydraulic-hammer strikers. To this end, we propose new design solutions for striking bodies that have the form of a body of revolution with an internal cavity with lateral surface generated by revolving a straight or hyperbolic line. Such a shape contributes to the formation of a force pulse consistent with the destruction mechanism. [ABSTRACT FROM AUTHOR]

In a virtual reality (VR) space, wearing a head-mounted display can help with the visualization of objects; however, users cannot experience realistic tactile sensations. Recently, several force feedback devices have been developed, including wearable devices that use straight-fiber-type pneumatic muscles and magnetorheological fluids. This allows the devices to render elastic, frictional, and viscous forces during spatially unrestricted movement. Nevertheless, a problem remains in that previous devices could handle many bilateral upper limb movement tasks. Therefore, this study aims to develop a device that can handle movements that interact with both arms. Based on experiments concerning the pushing motion in a VR space, the influence of the pseudo force sense was determined to not be small. In addition, we confirmed that the force sensation presented by this system was more realistic when the robot was operated with both arms than when operated with the right arm. [ABSTRACT FROM AUTHOR]

Background: Long-gap esophageal atresia (EA) is not amenable to primary anastomosis though the goal of surgical treatment is to restore the patency in the native esophagus; the Foker technique is one of the methods that can accomplish it. Case Presentation: This case series consists of three patients who presented with a type-A long-gap EA. Extrathoracic esophageal elongation was achieved using the Foker technique. During the first stage, we utilized pledgeted sutures reinforced with titanium clips for elongation that began five days after the surgery. As the elongation progressed, and the gap between esophageal pouches decreased, we restored the continuity of the esophagus. On follow-up, all patients needed pneumatic dilatation of the esophagus. Conclusion: The Foker technique successfully restored the esophageal continuity using the native esophagus in our patients with esophageal atresia. [ABSTRACT FROM AUTHOR]

The subject of this research is convergence technology for the surface finishing of vehicle parts. A literature review has been conducted to carry out a comparative analysis of existing methods for the surface finishing of parts used in the manufacturing of aircraft, hydraulic and pneumatic devices, and other vehicles. Prospects are shown for further research on methods with the aim of creating a complex technology (i.e., convergence) that combines information technologies; nanotechnologies; and thermochemical, electrochemical, and mechanical processing methods. A method is proposed for selecting and combining surface finishing methods according to a five-point expert assessment, which allows the batch processing of vehicle parts. Based on this method, the concept of convergence technology for the surface finishing of vehicle parts is proposed, which includes the impulse thermal energy method, honing, superfinishing, and electrochemical processing. An expanded process is presented for manufacturing parts with high-precision, low-roughness surfaces and a specified microrelief by using electrochemical superfinishing and electrochemical honing. A scheme of the concentration (focusing) of the current flow during electrochemical superfinishing due to the movement of the electrode relative to the part surface is proposed, which enables the effect of surface polishing and the removal of oxidation products. Convergence technology for the surface finishing of vehicle parts will provide parts' geometric dimensions with micro- and nano-precision and allow the precision machining of smalldiameter holes and complex profiles, increased machining accuracy (up to 0.001 microns), the possibility of batch processing, and the possibility of process automation. [ABSTRACT FROM AUTHOR]

To examine patient barriers to intermittent pneumatic compression (IPC) device compliance during antepartum hospital admissions. This was a prospective survey study of a diverse group of pregnant patients who were admitted to the antepartum floor in a quaternary care hospital from June 2019 through March 2021. Patients receiving pharmacotherapy for venous thromboembolism prophylactic or therapeutic indications were excluded. The primary outcome was patient reported barriers to use of IPC during antepartum hospital admission. Responses were summarized using descriptive statistics. A total of 40 patients were surveyed. All participants correctly identified the purpose of IPC. When asked regarding IPC importance, 7.5% reported not important, 40% reported somewhat important but not a priority, 5% important only on the first day they were given, and 47.5% reported important whenever the patient was in bed. The most bothersome characteristics of IPC use identified by the respondents on a Likert scale from 1 to 5 were sweating, made the legs too hot, restricted movement, and inconvenience and time spent putting on and taking off the IPC. Making the device wireless/cordless (77.5%), using a lighter weight or cooler material for the cuffs (55%), and better availability of nurses to assist with putting on, taking off, and troubleshooting the IPC (17.5%) were identified by patients as ways to increase compliance with IPC. This survey identified several modifiable barriers to the use of IPC on the antepartum floor. [ABSTRACT FROM AUTHOR]

Metal single droplets are widely used in electronic packaging and flexible circuit printing. However, liquid metals are characterized by high density and interfacial tension, so that stable injection of single droplet occurs only in an extremely small printable region, which limits the application of metal droplets. In this study, based on a drop-on-demand pneumatic injection device, the evolutionary process and mechanism of metal droplet generation are analyzed through experiments and numerical simulations, the theoretical solution of the injection velocity is obtained, the printable region that can stably generate the single droplet dimensionless parameters Wej (Jet Weber number) and Z (1/Ohnesorge number) is plotted, and the prediction model of the single droplet dimensionless limit jet length is established. Results show that in the range 400 < Z < 1100, the printable region where single droplets can be generated is extremely narrow (1.3 < Wej < 2). When Wej < 1.3, the inertial force of the jet is not sufficient to overcome the interfacial capillary force, and no droplets can be generated. When Wej > 2, the inertial force of the jet is so large that satellite droplets are generated. The prediction results obtained by the prediction model of single droplet dimensionless limit jet length are consistent with the experimental results and can accurately predict whether a single droplet can be generated or not. The results can reveal the mechanism of stable generation of on-demand pneumatic metal droplets. Furthermore, the results can serve as theoretical references for the further development of on-demand pneumatic metal droplet injection technology. [ABSTRACT FROM AUTHOR]

This research is focused on the evaluation of cutting edge wear of the delimbing knife by contactless methods. Delimbing knives were tested in an experimental device constructed in our laboratory, which operates on the principle of a forest harvester head. The greatest wear of the cutting edge was manifested in knife no. 1 with a blade angle of ∢ 7°. The research was focused on the wear of delimbing knives made of DIN 58SiCr8/WNr material when changing the angular geometry of the tool and using a constant delimbing speed of 2.0 m.s−1 while delimbing spruce wood of various wood diameters. The Alicona Infinite Focus device, which functions as a non-contact 3D optical device, was used to determine the amount of wear on the cutting edge of the knife. The size of cutting edge wear significantly affects chipless cutting wood, which can be observed in an increase in the cutting force during the delimbing process. The use of harvester technology in forestry is a highly topical issue today. From this point of view, it is necessary to focus on increasing the efficiency and reducing the energy consumption of the machine, which economically benefits its delimbing operation. [ABSTRACT FROM AUTHOR]

The paper presents an overview of the economic efficiency for linear drive with solenoid coupling. Moreover, the linear drive with solenoid coupling is also a pneumatic device. Thereby in this article, we are studying two pneumatic and one electro-pneumatic installation, which contains the linear drive with solenoid coupling. The first pneumatic circuit contains the following devices: compressed air supply, start-up valve with filter control valve, 4/2-way valve with spring, throttle valves, linear drive with solenoid coupling (LD 1-1). The second pneumatic circuit contains the following components: linear drives, throttle valves, 5/2-way valve, air service unit, compressed air supply. The last circuit which is actually an electro-hydraulic circuit contains the following components: compressed air supply, 5/2-way solenoid valve with spring, linear drive with solenoid coupling (LD 3-1), relays, valves solenoid and magnetic proximity switch. [ABSTRACT FROM AUTHOR]

To improve the seedling-picking efficiency of the vegetable transplanter and reduce the damage rate of the seedling pot, a reciprocating seedling-picking device driven by full air pressure was designed. In this paper, the structure and working principle of the pneumatic seedling-picking device are introduced. Through the mechanical analysis between the seedling-picking claw and the seedling pot, working parameters such as the stroke and driving force of the pneumatic seedling-picking claw clamping cylinder were determined. According to the action sequence of the seedling-picking mechanism, which is horizontally dispersed and longitudinally conveyed, the pneumatic control scheme of the seedling-picking and -dropping system was formulated. The simulation model for the control loop of the longitudinal cylinder was created with AMESim simulation software, and the simulation analysis was carried out. The Box–Behnken response surface design optimization method was used to determine the best operating parameters of the cylinder. The optimized peak value of shock vibration at the end of the cylinder was optimized from −65.64 mm·s−2 to 35.41 mm·s−2, proving that the optimization of pneumatic working parameters has a positive effect on the success rate of seedling picking. The bench test of the seedling-picking mechanism was conducted on 72-hole plug seedlings with two picking frequencies of 120 plants·min−1 and 144 plants·min−1, respectively, and the average seedling leakage rate, seedling damage rate, and seedling pot damage rate at different picking frequencies were counted. The experimental results show that under the two seedling-picking frequencies, the average success rate of seedling picking and throwing after optimization is increased from 96.4% and 92.4% to 97.9% and 95.3%, respectively. This is in line with the requirements of high-speed seedling picking and confirms the rationality of the seedling-picking mechanism design. [ABSTRACT FROM AUTHOR]

Electromagnetic mini valves have attracted great interest in medical devices for their excellent performance and high integration. In state-of-the-art research, most mini valves have only two working states, while certain ones featuring three to four working states necessitate multiple driving sources. To solve these problems, a novel tristable electromagnetic mini valve with three stable working states achieved by a single coil was proposed. The actuation mechanism of this mini valve mainly comprises a cylindrical magnet (CM) and a ring magnet (RM) coaxially arranged. In the absence of current through the coil, the stability of the magnets is upheld by their mutual repulsion and the attraction of the iron core. Upon modifying both the magnitude and orientation of the current, one of the magnets traverses from one terminus to another each time. The two magnets are either stationary at the start point or the endpoint. Thereby, four position relationships are formed, three of which are stable. The minimum response time and energy consumption are 3.75 ms and 0.013 J, respectively. The working pressure of the valve ranges from 0 to 200 kPa. The maximum flow rate and back pressure reach 10.5 L/min and 180 kPa, respectively. A tristable design contributes to lower energy consumption, and the three-working-state function actuated by a single coil facilitates a diminution in the size of the mini valve. Consequently, a diminished quantity of valves is realized for multiple degree-of-freedom pneumatic actuator control, which promotes the miniaturization of the whole system. The dimensions and performance of the proposed mini valve substantiate its potential in pneumatic medical devices. [Display omitted] • The three-way electromagnetic mini valve achieves three stable working states through a single coil drive. • A tristable design is realized by the attraction of the iron core and the repulsion between two magnets. • The CM flips during the transformation, thus forming four states, three stable working states and a transition state. • The considerable magnet repulsion keeps the magnets stable, thereby increasing the working pressure and back pressure. [ABSTRACT FROM AUTHOR]

In this study, a pneumatic cycle device, herein called the air-operated solid-phase extraction (AO-SPE), was designed for the enrichment of pharmaceutical residues. The device consisted of two parts: an air circulation system and an adsorption system. The continuous air flow ensured that the water sample flowed past the adsorbent, completing the adsorption process. One significant advantage of this device is that the air circulation system can generate pneumatic cycle adsorption with the continuous air flow, increasing the interaction between the adsorbent and the target analytes. Additionally, the entire device is easy to install and dismantle, and the adsorbent can be easily replaced, making the AO-SPE suitable for various types of adsorbents materials tailored to specific target analytes. The smart design is aimed at extracting trace analytes in the large-volume water samples. As a proof-of-concept, the AO-SPE was applied to enrich non-steroidal anti-inflammatory drugs in soil. A Ce-based metal organic framework composite was prepared and applied to verify the applicability of AO-SPE, exhibiting the enrichment factor of up to 538. The results showed that AO-SPE exhibited a maneuverable approach with high efficiency and sensitivity for analyzing large-volume samples, indicating a great potential for extracting of trace analytes. [Display omitted] • An air-operated solid-phase extraction device was developed. • The continuous air flow maintained the pneumatic cycle adsorption. • Ce-MOF coated cotton pieces was prepared as adsorbent for the assessment of AO-SPE. • The AO-SPE was suitable for sampling large-volume aqueous samples. [ABSTRACT FROM AUTHOR]

Background: During prolonged standing, insufficient calf muscle pumping accompanies venous stasis and hypertension in the lower legs, resulting in valve dysfunction, venous wall problems, and sub-sequent inflammation. Compression therapy, which includes medical compression stockings (MCS) and mechanical intermittent pneumatic compression (IPC), is one of the most effective therapeutic interventions for treating chronic venous diseases. This study aimed to compare the therapeutic effect among resting, IPC and MCS alone, and IPC with MCS in long-standing workers (> 8 h daily).Methods: This crossover trial was conducted with 39 participants with complaints of leg edema and pain whose work involved standing for more than 8 h daily. Four treatment protocols were established for each visit as follows: protocol A (not wear MCS during work and rest without IPC after work), protocol B (wear MCS during work and rest without IPC after work), protocol C (not wear MCS during work and treat with IPC after work), and protocol D (wear MCS during work and treat with IPC after work). The primary outcome was the visual analogue scale (VAS) score for leg pain. The secondary outcomes were leg volume (mL), circumference (cm), extracellular fluid/total body fluid (ECF/TBF), and extracellular water/total body water (ECW/TBW) through bioelectrical impedance analysis. Outcomes were assessed before work (T0), after work (T1), and 60 min after intervention (T2).Results: All four protocols had significantly increased leg pain after work (T0-1) but improved 60 min after intervention (T1-2), particularly protocol C (decreased VAS by 1.9). When leg swelling was compared at T0 and T1, protocols A and C showed significant increases in leg volume and circumference, indicating significant work-induced edema, whereas protocols B and D showed no change or even a decrease. After interventions, leg volume and circumference significantly decreased in protocols A and C, although protocols B and C did not show significant improvement. The ECF/TBF and ECW/TBW of all protocols decreased after interventions.Conclusions: Leg pain and edema after prolonged standing (T1-T2) in adults were safely and effectively improved by both IPC alone and IPC with MCS. Although the use of MCS during the workday did not show improvement in leg pain immediately after work (T0-T1), both MCS with resting and MCS with IPC decreased leg pain at T1-T2 and prevented leg edema at T0-T1.Trial Registration: This trial protocol was registered at the Clinical Research Information Service (KCT0005383, the date of first registration: 08/09/2020). [ABSTRACT FROM AUTHOR]

Background: Pharmacological and mechanical thromboprophylaxis are frequently used together after total knee arthroplasty (TKA). Most studies in this context compare anticoagulants versus a combination of these drugs with an intermittent pneumatic compression device (IPCD). However, there is uncertainty about the need for the combination of both and whether a unilateral IPCD would alone affect other important clinical outcomes: edema and blood loss. We compared the effects of enoxaparin versus unilateral portable IPCD after TKA on edema and blood loss. We hypothesised that unilateral IPCD would cause the same level of edema and the same blood loss as enoxaparin.Methods: In this open, randomized trial (1:1), adults with no history of coagulation disorders, anticoagulant use, venous thromboembolism, liver or malignant diseases underwent TKA. For 10 days, participants received the IPCD, used 24 h/day on the operated leg from the end of surgery, or 40 mg of enoxaparin, starting 12 h after surgery. All underwent the same rehabilitation and were encouraged to walk on the same day of surgery. We measured edema (thigh, leg and ankle circumference) before and on the third postoperative day. Blood loss (volume accumulated in the suction drain and drop of hemoglobin and hematocrit in 48 h) was a secondary outcome.Results: We randomized 150 patients and lost 3 to follow-up with enoxaparin and 2 with IPCD. There was no case of symptomatic venous thromboembolism. Four patients needed transfusions (three receiving enoxaparin), one had infection and one hemarthrosis (both in the enoxaparin group). Leg circumference increased by approximately 2 cm for enoxaparin group and 1.5 cm in IPCD (p <  0.001). The increase in ankle circumference was about 1.5 cm in the enoxaparin group (p <  0.001), and almost zero in IPCD (p = 0.447). Enoxaparin group lost 566.1 ml (standard deviation, SD, 174.5) of blood in the first 48 h, versus 420.8 ml (SD 142.5) in the IPCD.Conclusions: Exclusively mechanical prophylaxis after TKA with portable IPCD only on the operated leg reduces leg and ankle swelling and post-operative blood loss compared to exclusively pharmacological prophylaxis with enoxaparin. Portable devices that can prevent deep vein thrombosis and pulmonary embolism without increasing blood loss or other risks should be further investigated.Trial Registration: REBEC RBR-8k2vpx. Registration date: 06/04/2019. [ABSTRACT FROM AUTHOR]

Background : Compression bandages, stockings, and pneumatic compression devices are common classifications of compression products, used alone or in combination. The structure of these compression products is complex: they are typically multi-layered, overlapped, stretched and applied to a three-dimensional curved surface part of the body. This research aims to review the materials, designs, and fabrication processes/technologies of a variety of compression devices used in management of chronic edema by considering contributions of materials/textiles, as well as prototyping technologies. Method : Relevant papers/patents for review were identified using keywords associated with materials, designs, and fabrication processes of textile-based compression devices/products for treatments of the edematous lower limb. Results : Modern Compression therapies employ textile materials with a variety of fiber types, yarns and fabric structures, and wide range of elasticity and extensibility (i.e. inelastic to elastic, short stretch to long stretch) to provide the required pressure to the lower leg. Compression fabrics are fabricated using a variety of production technologies and machineries, and they have a wide range of physical and performance attributes. Conclusions : Appropriate selection of materials and fabrication technologies for use in compression therapy is essential to enhance the success in the management of chronic edema. This review might aid in the development and implementation of textiles/materials, and improvement in design of the textile-based compression devices to increase the efficacy of compression therapies in the management of chronic edema, allowing patients to improve their long-term health. [ABSTRACT FROM AUTHOR]

Objective: To assess a novel combined laser suction handpiece (LSH) for performing PCNL in a clinical setting. Methods: The study comprised 40 consecutive PCNLs performed between May 2019 and February 2020. The first 20 procedures (Group A) were performed with conventional ultrasonic or pneumatic devices and the other 20 (Group B) were performed with the use of the new LSH. All patients were treated by tubeless supine PCNL. The groups were compared for demographics, clinical data, operative time, lithotrite effectiveness, stone clearance rate (SCR), and outcome. Results: Groups A and B were similar in age, and in stone size, complexity, and density (Hounsfield units) (p < 0.05). The average operative time was 99 and 78 min, SCR 143 and 200 mm3/min, hospital stay 1.6 and 1.1 days, and stone-free rate 90% and 95%, respectively. Despite a trend toward better results with the new LSH, none of these comparisons reached statistical significance. Ineffective lithotripsy with the initial device (ultrasonic) requiring conversion to another modality (ballistic) occurred in six (30%) procedures in Group A, while all procedures were effectively accomplished with the LSH in Group B (p = 0.02). There were two complications in Group A and none in Group B (p > 0.05). Conclusions: The LSH is as effective and safe as the traditional lithotrites for performing PCNLs. This new tool completes the capabilities of the holmium laser high-power machines, enabling them to serve as the sole platform for all endourological treatments. [ABSTRACT FROM AUTHOR]

Pneumopercussion machines (pneumatic impact machines) are widely used in all areas of human activity. Also, they are widely used in the mining industry. Unfortunately, their operation is characterized by a low efficiency of compressed air energy usage. In some cases, this level of efficiency is calculated as 15-20%. Such a situation increases the cost of drilling operations significantly. In this article, due to an implementation of a new construction of the equipment, the efficiency of the pneumopercussion machines was increased. This problem is solved by combining the most effective thermodynamic processes of compressed air in the working chambers of machines. Also, a new technical solution for the construction of pneumopercussion machines is suggested by the Authors. The proposed new design is realized by a combination of the most effective thermodynamic processes in the chambers of pneumatic impact machines. A new pneumatic hammer is presented, which allows to reduce compressed air consumption twice during an operation on the surface (in comparison with hammers available on the market). The operation of pneumopercussion machines and the method of calculating geometric parameters are described. The economic performance of the equipment confirms the correctness of the proposed technological solutions. [ABSTRACT FROM AUTHOR]

The seeding performance of a pneumatic seed-metering equipment for rapeseed has a significant bearing on the sowing effect. When the negative pressure falls abruptly, the pneumatic system experiences a significant loss of negative pressure. This will prevent rapeseed from being entirely absorbed by the seed plate, resulting in inconsistent seeding quantities along each row. In this study, CFD simulations were used to analyze the airflow field affecting the airflow transmission of an airflow distribution device. The essential structural characteristics of a conical cylinder conical-arranged kind of airflow distribution device were found, and the causes of negative pressure loss were analyzed from the standpoint of fluid kinematics. The optimal structural type of airflow distribution device was determined using fluid simulation. In addition, an orthogonal examination of the ideal type's essential structural characteristics was conducted to minimize negative pressure loss during airflow transmission. Then, the influence of the negative pressure loss rate of the airflow distribution device on the variation coefficient of seeding quantity in each row of the seed-metering device was investigated using a bench test involving three factors: seed plate rotational speed, working negative pressure, and structure type. It was discovered that three parameters have highly substantial impacts on the negative pressure loss rate and the variation coefficient of seeding quantity in each row, and that the negative pressure loss rate correlates positively with the variation coefficient of the seeding quantity in each row. When negative pressure fell to 500 Pa, the negative pressure loss rate of the optimal structure type and the variation coefficient of seeding amount in each row of the seed-metering device fell by 6.25% and 3.45%, respectively. Field experiments reveal that the negative pressure loss rate of an airflow distribution device was below 20% and that the variation coefficient of seeding amount in each row of seed-metering devices was below 3.5%. The results can be used to analyze the construction of the pneumatic system and enhance the performance of the seed-metering equipment. [ABSTRACT FROM AUTHOR]

Generating and maintaining the concentration dilutions of diffusible molecules in microchannels is critical for high-throughput chemical and biological analysis. Conventional serial network microfluidic technologies can generate high orders of arbitrary concentrations by a predefined microchannel network. However, a previous design requires a large occupancy area and is unable to dynamically generate different profiles in the same chip, limiting its applications. This study developed a microfluidic device enabling dynamic variations of both the concentration in the same channel and the concentration distribution in multiple channels by adjusting the flow resistance using programmable pneumatic microvalves. The key component (the pneumatic microvalve) allowed dynamic adjustment of the concentration profile but occupied a tiny space. Additionally, a Matlab program was developed to calculate the flow rates and flow resistance of various sections of the device, which provided theoretical guidance for dimension design. In silico investigations were conducted to evaluate the microvalve deformation with widths from 100 to 300 µm and membrane thicknesses of 20 and 30 µm under the activation pressures between 0 and 2000 mbar. The flow resistance of the deformed valve was studied both numerically and experimentally and an empirical model for valve flow resistance with the form of R h = a e b P was proposed. Afterward, the fluid flow in the valve region was characterized using Micro PIV to further demonstrate the adjustment mechanism of the flow resistance. Then, the herringbone structures were employed for fast mixing to allow both quick variation of concentration and minor space usage of the channel network. Finally, an empirical formula-supported computational program was developed to provide the activation pressures required for the specific concentration profile. Both linear ( C k = −0.2k + 1) and nonlinear (C k = (1 10 ) k) concentration distribution in four channels were varied using the same device by adjusting microvalves. The device demonstrated the capability to control the concentration profile dynamically in a small space, offering superior application potentials in analytical chemistry, drug screening, and cell biology research. [ABSTRACT FROM AUTHOR]

Unmanned Aerial Vehicles (UAVs) have been widely used in rice direct seeding in recent years, due to the flexibility and high efficiency suitable for the terrain. Among them, UAV broadcast sowing has been one of the most UAV rice direct seeding, particularly with better seeding uniformity and work efficiency, compared with manual seeding. The broadcast sowing device can also be divided into the centrifugal disc and pneumatic types in China at present. However, the UAV broadcast sowing is easily affected by the rotor wind field, leading to uneven seeding. At the same time, the effect of seeding in the rows and holes can also result in air permeability and occurrence of diseases during the growth of rice in field management. In this study, a control system was designed for the rice shot seeding device in a flight controller order, in order to improve the uniformity and the accuracy of the seeding rate during UAV rice direct seeding. A UAV ground station function was also established to develop the experimental prototype. A closed-loop control was realized in the speed of the stepping motor using the Proportion Integral Derivative (PID). The calibration was then conducted to evaluate the excitation force of the vibration motor and the speed of the friction wheel motor. Finally, the seeding control program was designed to control the whole process of rice shot seeding using a Finite State Machine. The control functions included operation route planning, seeding rate calibration, parameter setting, seed remaining quantity display, and automatic seeding, in order to more easily realize the automatic operation of rice direct seeding. Taking three-fold pelleted rice seeds as the seeding objects, the seeding performance of the prototype was verified from three aspects: the accuracy of the seeding rate, the row effect, and seeding uniformity. The results showed that the average relative error of the seeding rate was less than 4% when the prototype flew at the speed of 1.0-2.5 m/s under the simulation. An excellent performance was achieved in the dynamic adjustment for the seeding control system, particularly with the relatively accurate seeding rate. Specifically, the average probability of seeds was 75.18% within the seed row width of 15 cm, when the prototype was seeding at the height of 2.0 m. By contrast, the average probability of seeds was higher than 80% within the seed row width of 12 cm, when the prototype seeding at the height of 1.0 and 1.5 m, indicating the better performance of the seeding row. Correspondingly, the working height of 1.5 m was preferred, in terms of safety. The average Coefficient of Variation (CV) of seeding uniformity was 20.51%-35.52% when the prototype worked at the height of 1.5 m with a speed of 0.5-2.0 m/s, and the seeding rate of three-fold pelleted rice seed of 90-150 kg/hm2 (corresponding to the seeding rate of naked seeds was 22.5-37.5 kg/hm2 ). It infers that the working speed greatly contributed to the seeding uniformity. Two field experiments were carried out, according to the preferred seeding parameters, where the relative errors of the seeding rate were 2.47% and 4.12%, respectively, the seeding uniformity CV values were 22.17% and 21.82%, respectively, and the seed breakage rates were 0.34% and 0.18%, respectively. The seeding control system fully met the control accuracy requirements of UAV rice direct seeding, according to the standard Technical specification of quality evaluation for the aerial broadcast seeder by remote control (standard NY/T 3881-2021). This finding can provide a strong reference for the UAV rice direct seeding. [ABSTRACT FROM AUTHOR]