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1.
Artif Organs ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39221585

RESUMEN

BACKGROUND: To accommodate a wider range of medical device sizes, a larger in vitro flow loop thrombogenicity test system using 9.5 -mm inner diameter (ID) tubing was developed and evaluated based on our previously established 6.4 -mm ID tubing system. METHODS: Four cardiopulmonary bypass roller pumps were used concurrently to drive four flow loops during testing. To ensure that each pump produced a consistent thrombogenic response for the same material under the same test conditions, a novel dynamic roller occlusion setting method was applied. Five materials with varying thrombogenic potentials were tested: polytetrafluoroethylene (PTFE), silicone, 3D-printed nylon, latex, and nitrile rubber (BUNA). Day-old bovine blood was heparinized to a donor-specific concentration and recirculated through the flow loops containing test materials at 20 rpm for 1 h at room temperature. Material thrombogenicity was characterized by measuring the thrombus surface coverage, thrombus weight, and platelet (PLT) count reduction. RESULTS: The larger tubing system can differentiate thrombogenic materials (latex, BUNA) from the thromboresistant PTFE material. Additionally, silicone and the 3D-printed nylon exhibited an intermediate thrombogenic response with significantly less thrombus surface coverage and PLT count reduction than latex and BUNA but more thrombus surface coverage than PTFE (p < 0.05). CONCLUSION: The 9.5 -mm ID test system can effectively differentiate materials of varying thrombogenic potentials when appropriate pump occlusion settings and donor-specific anticoagulation are used. This system is being assessed in an interlaboratory study to develop standardized best practices for performing in vitro dynamic thrombogenicity testing of medical devices and materials.

2.
Data Brief ; 56: 110798, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39234053

RESUMEN

This dataset presents 9596 photos of the East and West façades of a university building in Barcelona (Spain). Images were taken every hour for one year with two identical GoPro Hero 10 cameras. The façades are composed of a grid of 28×7 windows in the East and 28×6 windows in the West. Every window has a portion of fixed glass and an operable part for natural ventilation, and mobile solar protections (roller shutters) that users can control manually. These images are of special interest due to the lack of observation data on the user-building interaction with manually controlled adaptive façades. These data are a valuable source of information for interpreting and understanding the actual use of manually controlled adaptive façades, as well as developing usage models that could be implemented in energy simulations. Also, cropping all the windows from the full-façade photos result in 1.7 M images of individual windows, which can be easily used as a computer vision and machine learning exercise to read the position of the solar protections or the operable part of the windows.

4.
Ecol Evol ; 14(7): e11557, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38983707

RESUMEN

Golden-winged Warblers (Vermivora chrysoptera) have become rare across much of their historic breeding range and response to conservation efforts is variable. Evidence from several recent studies suggests that breeding output is a primary driver explaining responses to conservation and it is hypothesized that differences in food availability may be driving breeding output disparity between two subpopulations of the warbler's Appalachian breeding range. Herein, we studied two subpopulations: central Pennsylvania ("central subpopulation"), where breeding productivity is relatively low, and eastern Pennsylvania ("eastern subpopulation"), where breeding productivity is relatively high. To test the food-availability hypothesis in this system, we measured density of caterpillars, plasma lipid metabolites (triglycerides [TRIG; fat deposition] and glycerol [GLYC; fat breakdown]), body mass of adults males, and acquired body mass data for fledglings at 38 sites managed for nesting habitat. Consistent with our prediction, leaf-roller caterpillar density, the group upon which Golden-winged Warblers specialize, was 45× lower in the central subpopulation than the eastern subpopulation. TRIG concentrations were highest within the eastern subpopulation during breeding grounds arrival. The change in TRIG concentrations from the breeding-grounds-arrival stage to the nestling-rearing stage was subpopulation dependent: TRIG decreased in the eastern subpopulation and was constant in the central subpopulation, resulting in similar concentrations during the nestling-rearing stage. Furthermore, GLYC concentrations were higher in the eastern subpopulation, which suggests greater energy demands in this region. Despite this, adult male warblers in the eastern subpopulation maintained a higher average body mass. Finally, fledgling body mass was 16% greater in the eastern subpopulation than the central subpopulation before and after fledging. Collectively, our results suggest that poor breeding success of Golden-winged Warblers in the central subpopulation could be driven by lower availability of primary prey during the breeding season (leaf-roller caterpillars), and this, in turn, limits their response to conservation efforts.

5.
Sensors (Basel) ; 24(13)2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-39001187

RESUMEN

As an important vehicle in road construction, the unmanned roller is rapidly advancing in its autonomous compaction capabilities. To overcome the challenges of GNSS positioning failure during tunnel construction and diminished visual positioning accuracy under different illumination levels, we propose a feature-layer fusion positioning system based on a camera and LiDAR. This system integrates loop closure detection and LiDAR odometry into the visual odometry framework. Furthermore, recognizing the prevalence of similar scenes in tunnels, we innovatively combine loop closure detection with the compaction process of rollers in fixed areas, proposing a selection method for loop closure candidate frames based on the compaction process. Through on-site experiments, it is shown that this method not only enhances the accuracy of loop closure detection in similar environments but also reduces the runtime. Compared with visual systems, in static positioning tests, the longitudinal and lateral accuracy of the fusion system are improved by 12 mm and 11 mm, respectively. In straight-line compaction tests under different illumination levels, the average lateral error increases by 34.1% and 32.8%, respectively. In lane-changing compaction tests, this system enhances the positioning accuracy by 33% in dim environments, demonstrating the superior positioning accuracy of the fusion positioning system amid illumination changes in tunnels.

6.
Sensors (Basel) ; 24(14)2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39065861

RESUMEN

The performance-degradation pattern of the planetary roller screw mechanism (PRSM) is difficult to predict and evaluate due to a variety of factors. Load-carrying capacity, transmission accuracy, and efficiency are the main indicators for evaluating the performance of the PRSM. In this paper, a testing device for the comprehensive performance of the PRSM is designed by taking into account the coupling relationships among temperature rise, vibration, speed, and load. First, the functional design and error calibration of the testing device were conducted. Secondly, the PRSM designed in the supported project was taken as the research object to conduct degradation tests on its load-bearing capacity and transmission accuracy and analyze the changes in transmission efficiency. Third, the thread profile and wear condition were scanned and inspected using a universal tool microscope and an optical microscope. Finally, based on the monitoring module of the testing device, the vibration status during the PRSM testing process was collected in real time, laying a foundation for the subsequent assessment of the changes in the performance state of the PRSM. The test results reveal the law of performance degradation of the PRSM under the coupled effects of temperature, vibration, speed, and load.

7.
Food Res Int ; 191: 114590, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39059891

RESUMEN

Sanitizer spray and brush roller treatments have been documented as an effective means of reducing Salmonella on the surface of produce. The purpose of this study was to evaluate the efficacy of chlorine (NaOCl), peroxyacetic acid (PAA), and chlorine dioxide (ClO2) sprays to reduce Salmonella populations on the surface of mangoes during washing with brush or polyvinyl chloride (PVC) rollers. Whole mangoes were spot inoculated with 100 µL of a rifampicin-resistant Salmonella (8 log CFU/mL) cocktail at the equator and dried for 1 h. Mangoes were washed with a lab-scale roller system with either ground water (control), or sanitizers (100 ppm NaOCl, 80 ppm PAA, or 5 ppm ClO2) for 0, 5, 15, 30, or 60 s (n = 15 mangoes). Dey/Engley buffer (100 mL) was used to rinse mangoes before plating on media supplemented with rifampicin. NaOCl, PAA, and ClO2 spray (except for ClO2 at 30 s) had significantly higher reduction on Salmonella population than water spray at all treatment times (P ≤ 0.05) when brush rollers were used. All tested sanitizers also achieved a significantly higher reduction than water at 5 s when PVC rollers were used (P ≤ 0.05). Salmonella reductions achieved by brush and PVC rollers was not statistically different (P > 0.05). After a 5 s treatment on brush and PVC rollers, NaOCl, PAA, and ClO2 spray had ca. 3.03 and 3.45 log, 3.96 and 3.28 log, and 2.54 and 2.00 log CFU/mango reductions, respectively, whereas water spray achieved 1.75 and 0.98 log CFU/mango reduction. Addition of sanitizers to spray water used during brush or PVC washing in mango packinghouses can reduce Salmonella on mango surfaces.


Asunto(s)
Compuestos de Cloro , Recuento de Colonia Microbiana , Desinfectantes , Mangifera , Óxidos , Ácido Peracético , Cloruro de Polivinilo , Salmonella , Hipoclorito de Sodio , Mangifera/microbiología , Compuestos de Cloro/farmacología , Salmonella/efectos de los fármacos , Desinfectantes/farmacología , Óxidos/farmacología , Ácido Peracético/farmacología , Hipoclorito de Sodio/farmacología , Manipulación de Alimentos/métodos , Microbiología de Alimentos
8.
Materials (Basel) ; 17(12)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38930323

RESUMEN

This paper presents a comprehensive study of the impact of quenching roll speed on enhancing the low-temperature toughness of a low-carbon copper-containing steel. The microstructure characteristics, such as the prior austenite grains, and the distribution and volume fraction of precipitates, are observed using optical microscopy, scanning electron microscopy, transmission electron microscopy, and small-angle scattering X-ray. The results show that a decrease in the quenching roller speed (2 m/min) contributes to the achievement of more excellent low-temperature toughness (the average value is 232 J), although the prior austenite grains exhibit a relatively larger size in this case. The tempering treatment results in the precipitation of a large amount of 9R-type Cu-rich particles, regardless of the quenching roller speed. Reducing the quenching roller speed contributes to the increase in the volume fraction of Cu-rich particles, which is considered to be the main factor contributing to the achievement of excellent low-temperature toughness.

9.
Int J Mol Sci ; 25(11)2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38892174

RESUMEN

Foodborne diseases can be attributed not only to contamination with bacterial or fungal pathogens but also their associated toxins. Thus, to maintain food safety, innovative decontamination techniques for toxins are required. We previously demonstrated that an atmospheric-pressure dielectric-barrier discharge (APDBD) plasma generated by a roller conveyer plasma device is effective at inactivating bacteria and fungi in foods. Here, we have further examined whether the roller conveyer plasma device can be used to degrade toxins produced by foodborne bacterial pathogens, including aflatoxin, Shiga toxins (Stx1 and Stx2), enterotoxin B and cereulide. Each toxin was spotted onto an aluminum plate, allowed to dry, and then treated with APDBD plasma applied by the roller conveyer plasma device for different time periods. Assessments were conducted using a competitive enzyme-linked immunosorbent assay (ELISA) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results demonstrate a significant time-dependent decrease in the levels of these toxins. ELISA showed that aflatoxin B1 concentrations were reduced from 308.6 µg/mL to 74.4 µg/mL within 1 min. For Shiga toxins, Stx1 decreased from 913.8 µg/mL to 65.1 µg/mL, and Stx2 from 2309.0 µg/mL to 187.6 µg/mL within the same time frame (1 min). Enterotoxin B levels dropped from 62.67 µg/mL to 1.74 µg/mL at 15 min, and 1.43 µg/mL at 30 min, but did not display a significant decrease within 5 min. LC-MS/MS analysis verified that cereulide was reduced to below the detection limit following 30 min of APDBD plasma treatment. Taken together, these findings highlight that a range of foodborne toxins can be degraded by a relatively short exposure to plasma generated by an APDBD using a roller conveyer device. This technology offers promising advancements in food safety, providing a novel method to alleviate toxin contamination in the food processing industry.


Asunto(s)
Presión Atmosférica , Espectrometría de Masas en Tándem , Enterotoxinas , Depsipéptidos/química , Microbiología de Alimentos/métodos , Cromatografía Liquida/métodos , Enfermedades Transmitidas por los Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/microbiología , Ensayo de Inmunoadsorción Enzimática , Contaminación de Alimentos/análisis , Gases em Plasma/química , Aflatoxina B1
10.
Int J Pharm ; 660: 124366, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-38901541

RESUMEN

This research investigates the modeling of the pharmaceutical roller compaction process, focusing on the application of the Johanson model and the impact of varying roll speeds from 1 to 15 RPM on predictive accuracy of ribbon solid fraction. The classical Johanson's model was integrated with a dwell time parameter leading to an expression of a floating correction factor as a function of roll speed. Through systematic analysis of the effect of different roll speeds on the solid fraction of ribbons composed of microcrystalline cellulose, lactose, and their blends, corrective adjustment to the Johanson model was found to depend on both roll speed and formulation composition. Interestingly, the correction factor demonstrated excellent correlation with the blend's mechanical properties, namely yield stress (Py) and elastic modulus (E0), representative of the deformability of the powder. Validated by a multicomponent drug formulation with ±0.4-1.3 % differences, the findings underscore the utility of this modified mechanistic approach for precise prediction of ribbon solid fraction when Py or E0 is known for a given blend. Hence, this work advances the field by offering early insights for more accurate and controllable roller compaction operations during late-stage pharmaceutical manufacturing.


Asunto(s)
Celulosa , Composición de Medicamentos , Excipientes , Lactosa , Polvos , Celulosa/química , Lactosa/química , Composición de Medicamentos/métodos , Excipientes/química , Polvos/química , Química Farmacéutica/métodos , Módulo de Elasticidad
11.
Sci Rep ; 14(1): 12144, 2024 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802553

RESUMEN

Pain in the lower back is a major concern in today's era due to prolonged sitting in two-wheeler riders, mainly due to hamstring tightness. It also creates physical disability and impairment in activities of daily living. The study aimed to compare the efficacy of muscle energy technique (MET) and self-myofascial release (SMFR) using the foam roller on hamstring flexibility, dynamic balance, and physical disability amongst two-wheeler riders with chronic low back pain (LBP). Participants were randomized into two intervention groups, MET and SMFR using the envelope method, with each group having 20 participants. Hamstring flexibility and range of motion for knee extension and the lower back were assessed using the active knee extension test (AKE-L and AKE-R) and sit and reach test (SRT), while the dynamic balance was assessed by the star excursion balance test (SEBT) and physical disability by Roland-Morris Disability Questionnaire, (RMDQ). Measurements were taken at baseline and after 4 weeks of intervention. This study demonstrated that both SMFR using a foam roller and MET are effective in enhancing hamstring muscle flexibility, (SRT-F(1, 38) = 299.5, p < 0.001; AKE-R-F(1, 38) = 99.53, p < 0.001; AKE-L-F(1, 38) = 89.67, p < 0.001). Additionally, these techniques significantly improved dynamic balance in various directions, including anterior (ANT), anteromedial (AMED), medial (MED), posteromedial (PMED), posterior (POST), posterolateral (PLAT), lateral (LAT), and anterolateral (ALAT) directions (p < 0.01). Furthermore, there was a significant reduction in physical disability (RMDQ-F(1, 38) = 1307, p < 0.001), among two-wheeler riders suffering from chronic LBP. Compared to MET, SMFR using foam rollers was found to be more effective in enhancing hamstring flexibility, improving balance, and decreasing disability level on the RMDQ after 4 weeks.


Asunto(s)
Músculos Isquiosurales , Dolor de la Región Lumbar , Rango del Movimiento Articular , Humanos , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/fisiopatología , Masculino , Adulto , Femenino , Músculos Isquiosurales/fisiopatología , Adulto Joven
12.
Environ Toxicol Chem ; 43(8): 1836-1843, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38771171

RESUMEN

Neonicotinoids are insecticides used worldwide in phytosanitary and biocidal products and veterinary pharmaceuticals. Recently, some restrictions and bans have been imposed due to their adverse effects on nontarget invertebrates, including pollinators. Although they may have direct and indirect effects on wild vertebrates, few studies have assessed exposure to these compounds in wild birds, so our knowledge remains limited. In the present pilot study we have assessed the prevalence of seven neonicotinoid insecticides and some of their metabolites in whole blood samples from 19 European roller (Coracias garrulus) nestlings and five adult common kestrels (Falco tinnunculus) in an area treated with neonicotinoids to control the palm weevil (Rynchophorus ferrugineus) in southeastern Spain. One European roller nestling born in a palm tree was positive for thiamethoxam, with a concentration of 2.26 ng mL-1, but no residues of neonicotinoids or their metabolites were found in adult common kestrels. Future studies are needed to elucidate potential exposure to neonicotinoids at different times of the year. To our knowledge, this is the first report of the presence of thiamethoxam residues in whole blood of a wild bird species after its ban in Spain. Environ Toxicol Chem 2024;43:1836-1843. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Asunto(s)
Aves , Monitoreo del Ambiente , Insecticidas , Tiametoxam , Tiametoxam/análisis , Tiametoxam/metabolismo , Insecticidas/análisis , Insecticidas/metabolismo , Aves/metabolismo , España , Agricultura , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/metabolismo , Gorgojos , Neonicotinoides/análisis , Neonicotinoides/metabolismo , Medición de Riesgo
13.
J Pharm Sci ; 113(8): 2484-2491, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38763415

RESUMEN

This study introduces a modification to the roller compaction model proposed by Sousa et al.1 to account for the effect of roll speed on powder compaction in the dry granulation process. The proposed model enhances the prediction accuracy, particularly at higher roll speeds, which are often overlooked in existing models. The modified model is validated using literature data, demonstrating improved performance compared to the original model. Additionally, the model is applied to a pharmaceutical formulation, showing its applicability in an industrial context. The integration of the model into gPROMS allows for global sensitivity analysis and design space exploration, providing valuable insights for process optimization and scale-up. The study contributes to the understanding of roller compaction dynamics and offers a practical tool for decision-making in pharmaceutical manufacturing.


Asunto(s)
Polvos , Polvos/química , Composición de Medicamentos/métodos , Tamaño de la Partícula , Excipientes/química , Tecnología Farmacéutica/métodos , Química Farmacéutica/métodos , Modelos Teóricos
14.
Animals (Basel) ; 14(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731322

RESUMEN

Teeth grinding in suckling piglets is performed on many farms to protect the piglets' littermates and the sow's udder from injuries caused by the piglets' canines and third incisors. In this study, the effects of two teeth-grinding methods on the piglets' dental health and welfare were investigated. The piglets of a litter were evenly assigned to a treatment: one-third of littermates were ground with a roller grinding head (RG), one-third with a teacup grinding head (TCG), and one-third were not ground at all (CG). A random sample of 100 animals each from the RG and TCG treatment was examined for tooth injuries, i.e., dental pulp openings. Additionally, behavioural analysis was performed (n = 650 piglets), and skin lesions, growth and mortality were determined (n = 1565 piglets). TCG piglets had a lower risk (p < 0.001) of pulp opening than RG piglets (0.08 ± 0.31 vs. 2.67 ± 1.67 opened pulps per piglet). Mortality, growth, skin lesions and behaviour of piglets were not influenced by treatment (p > 0.05). This study showed that both teeth-grinding methods led to pulp openings. If teeth grinding cannot be avoided on a farm, using the teacup grinding head is recommended concerning animal health and welfare.

15.
Heliyon ; 10(8): e29835, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38699756

RESUMEN

Garlic (Allium Sativum L.) is a valuable root crop that can be utilized to season foods and is widely utilized in Ethiopia to treat many different kinds of diseases. The cloves are separated by hand for plantation and processing functions. This technique can be very exhausting and take a lot of time. To fill this gap, a garlic bulb-breaking machine was fabricated and tested with the clove variety grown in Holeta, Ethiopia. The major component of the machine is two rollers that revolve in opposing directions, and shearing the bulbs to separate the cloves. The performance test experiments were carried out in a full factorial design with feed rate as the first factor having three levels (3.7, 4.2, and 5.2 kg/min) and roller speed as a second factor with also three levels (276, 326, and 376 rpm). All tests were done at 66 % moisture content of garlic and 19 mm clearance between the breaking rollers. The interaction effect of the two factors shows an important difference (p < 0.05) in machine performance. The maximum breaking efficiency of (87.05 %) occurred at a feed rate (4.2 kg/min) and roller speed (326 rpm). Likewise, the maximum breaking capacity (306.98 kg/h) was recorded for the highest (5.2 kg/min) feed rate regardless of the 276 rpm roller speed. The minimum clumps of cloves (10.27 %) were obtained at combinations of 4.2 kg/min and 326 rpm. The lowest values of damaged cloves (1.79 %) and fuel consumption (5.61 ml/kg) were observed for the combination of the 3.7 kg/min with the 276.85 rpm whereas the maximum clove damage (2.29 %) was at the 5.2 kg/min feed rate combined with the maximum roller speeds (376 rpm). Therefore, the machine could be operated at the combination of 4.2 kg/min and 326 rpm for best performance in the majority of the parameters.

16.
Int J Pharm ; 658: 124201, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38705250

RESUMEN

The pharmaceutical industry has been shifting towards the application of mechanistic modeling to improve process robustness, enable scale-up, and reduce time to market. Modeling approaches have been well-developed for processes such as roller compaction, a continuous dry granulation process. Several mechanistic models/approaches have been documented with limited application to high drug-loaded formulations. In this study, the Johanson model was employed to optimize roller compaction processing and guide its scale-up for a high drug loaded formulation. The model was calibrated using a pilot-scale Minipactor and was validated for a commercial-scale Macropactor. Global sensitivity analysis (GSA) was implemented to determine the impact of process parameter variations (roll force, gap, speed) on a quality attribute [solid fraction (SF)]. The throughput method, which estimates SF values of ribbons using granule production rate, was also studied. The model predicted SF values for all 14 Macropactor batches within ± 0.04 SF. The throughput method estimated SF with ± 0.06 SF for 7 out of 11 batches. GSA confirmed that roll force had the largest impact on SF. This case study represents a process modeling approach to build quality into the products/processes and expands the use of mechanistic modeling during drug product development.


Asunto(s)
Composición de Medicamentos , Composición de Medicamentos/métodos , Composición de Medicamentos/instrumentación , Tecnología Farmacéutica/métodos , Modelos Teóricos , Excipientes/química , Tamaño de la Partícula , Química Farmacéutica/métodos
17.
Sci Rep ; 14(1): 11226, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38755223

RESUMEN

To establish the sound quality evaluation model of roller chain transmission system, we collect the running noise under different working conditions. After the noise samples are preprocessed, a group of experienced testers are organized to evaluate them subjectively. Mel frequency cepstral coefficient (MFCC) of each noise sample is calculated, and the MFCC feature map is used as an objective evaluation. Combining with the subjective and objective evaluation results of the roller chain system noise, we can get the original dataset of its sound quality research. However, the number of high-quality noise samples is relatively small. Based on the sound quality research of various chain transmission systems, a novel method called multi-source transfer learning convolutional neural network (MSTL-CNN) is proposed. By transferring knowledge from multiple source tasks to target task, the difficulty of small sample sound quality prediction is solved. Compared with the problem that single source task transfer learning has too much error on some samples, MSTL-CNN can give full play to the advantages of all transfer learning models. The results also show that the MSTL-CNN proposed in this paper is significantly better than the traditional sound quality evaluation methods.

18.
J Exerc Rehabil ; 20(2): 76-82, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38737466

RESUMEN

The purpose of this study was to investigate the immediate effects of vibration foam rolling on dorsiflexion range of motion (ROM), balance, and gait in stroke patients. Thirty stroke patients volunteered to participate and were randomly assigned to the vibrating foam roller group (n=15) and the foam roller group (n=15). The vibrating foam roller group performed a 30-min foam roller exercise program, with participants subjected to vibration at 28 Hz. The foam roller group performed the same exercise program as the vibrating foam roller group, but without vibration. Dorsiflexion lunge test, limits of stability, and Timed Up and Go were used to evaluate dorsiflexion ROM, balance, and gait before and after each intervention. The results revealed that the vibration foam roller group showed significant differences in dorsiflexion ROM and gait after the intervention, while the foam roller group exhibited a significant difference only in dorsiflexion ROM (P<0.05). In comparisons between the vibration foam roller group and the foam roller group, significant differences were observed in dorsiflexion ROM and gait (P<0.05). However, there were no significant differences in balance, both before and after the intervention, as well as in the comparisons between the two groups (P>0.05). This study confirmed that a single-session vibrating foam roller exercise program improves dorsiflexion ROM and gait in stroke patients. Further studies with extended exercise program durations are needed to address limitations and explore long-term effects.

19.
Heliyon ; 10(7): e28729, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38596086

RESUMEN

Resource efficient processing of polymers is of paramount importance to minimize energy consumption, processing time, and material losses in the polymer industry. This study is concerned with polymer processing in planetary roller extruders. A three-dimensional numerical flow simulation was tailored to understand the polymer flow through the extruder in detail. Using the simulation software ANSYS Polyflow, we quantified both directly measurable process parameters, such as pressure build-up, and more intangible parameters, such as material shear. By varying operational and material parameters in a sensitivity analysis, we showed that the dynamics, material stress and pressure build-up are controlled primarily by the number of spindles and their rotational speed. Notably, this work provides the first successful validation of a 3D simulation of a polymer flow in a planetary roller extruder against actual experimental data. The simulation showed robust agreement between the simulated and experimental values, provided that a critical backpressure length is reached. This computational approach minimizes labor-intensive experimental testing in polymer processing.

20.
Sensors (Basel) ; 24(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38610347

RESUMEN

Roller bearings are critical components in various mechanical systems, and the timely detection of potential failures is essential for preventing costly downtimes and avoiding substantial machinery breakdown. This research focuses on finding and verifying a robust method that can detect failures early, without creating false positive failure states. Therefore, this paper introduces a novel algorithm for the early detection of roller bearing failures, particularly tailored to high-precision bearings and automotive test bed systems. The featured method (AFI-Advanced Failure Indicator) utilizes the Fast Fourier Transform (FFT) of wideband accelerometers to calculate the spectral content of vibration signals emitted by roller bearings. By calculating the frequency bands and tracking the movement of these bands within the spectra, the method provides an indicator of the machinery's health, mainly focusing on the early stages of bearing failure. The calculated channel can be used as a trend indicator, enabling the method to identify subtle deviations associated with impending failures. The AFI algorithm incorporates a non-static limit through moving average calculations and volatility analysis methods to determine critical changes in the signal. This thresholding mechanism ensures the algorithm's responsiveness to variations in operating conditions and environmental factors, contributing to its robustness in diverse industrial settings. Further refinement was achieved through an outlier detection filter, which reduces false positives and enhances the algorithm's accuracy in identifying genuine deviations from the normal operational state. To benchmark the developed algorithm, it was compared with three industry-standard algorithms: VRMS calculations per ISO 10813-3, Mean Absolute Value of Extremums (MAVE), and Envelope Frequency Band (EFB). This comparative analysis aimed to evaluate the efficacy of the novel algorithm against the established methods in the field, providing valuable insights into its potential advantages and limitations. In summary, this paper presents an innovative algorithm for the early detection of roller bearing failures, leveraging FFT-based spectral analysis, trend monitoring, adaptive thresholding, and outlier detection. Its ability to confirm the first failure state underscores the algorithm's effectiveness.

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