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1.
Curr Allergy Asthma Rep ; 24(8): 457-469, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39028396

RESUMO

PURPOSE OF REVIEW: Chronic inducible urticaria (CIndU) is a group of long-persisting and challenging to manage diseases, characterized by recurrent wheals and angioedema induced by definite triggers. In this review, we address recent findings on CIndU pathogenesis, diagnosis as well as its treatment, and we discuss novel potential targets that may lead to the development of more effective therapies for CIndU patients. RECENT ADVANCES: Meaningful advances in the understanding of its pathogenesis have been reported in the last decades. Novel CIndU-specific patient-reported outcome measures enable a closer and better evaluation of patients. CIndU is a hard-to-treat disease that highly impairs quality of life (QoL) of affected patients. Provocation tests allow to diagnose CIndU subtypes. The only licensed and recommended treatment for CIndU are second generation non-sedating H1-antihistamines, which lack efficacy in many cases. Omalizumab off-label use has been assessed in all types of CIndU with overall good outcomes. Promising emerging therapies currently assessed in chronic spontaneous urticaria are paving the path for novel treatments for CIndU.


Assuntos
Urticária Crônica , Omalizumab , Humanos , Urticária Crônica/tratamento farmacológico , Urticária Crônica/imunologia , Urticária Crônica/terapia , Omalizumab/uso terapêutico , Qualidade de Vida , Antialérgicos/uso terapêutico , Urticária/tratamento farmacológico , Urticária/etiologia , Urticária/diagnóstico , Urticária/imunologia , Urticária/terapia
2.
Materials (Basel) ; 17(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38894028

RESUMO

The compaction of asphalt pavement is a crucial step to ensure its service life. Although intelligent compaction technology can monitor compaction quality in real time, its application to individual asphalt surface courses still faces limitations. Therefore, it is necessary to study the compaction mechanism of asphalt pavements from the particle level to optimize intelligent compaction technology. This study constructed an asphalt pavement compaction model using the Discrete Element Method (DEM). First, the changes in pavement smoothness during the compaction process were analyzed. Second, the changes in the angular velocity of the mixture and the triaxial angular velocity (TAV) of the mortar, aggregates, and mixture during vibratory compaction were examined. Finally, the correlations between the TAV amplitude and the coordination number (CN) amplitude with the compaction degree of the mixture were investigated. This study found that vibratory compaction can significantly reduce asymmetric wave deformation, improving pavement smoothness. The mixture primarily rotates in the vertical plane during the first six passes of vibratory compaction and within the horizontal plane during the seventh pass. Additionally, TAV reveals the three-dimensional dynamic rotation characteristics of the particles, and the linear relationship between its amplitude and the pavement compaction degree aids in controlling the compaction quality of asphalt pavements. Finally, the linear relationship between CN amplitude and pavement compaction degree can predict the stability of the aggregate structure. This study significantly enhances quality control in pavement compaction and advances intelligent compaction technology development.

3.
Materials (Basel) ; 17(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38930293

RESUMO

The grinding process plays a crucial role in industry, allowing for the reduction of particle sizes of raw materials and substances to the required fineness-either as a finished product or for further technological processes. The high demand for micro- and nanopowders or suspensions is associated with the high energy consumption of the milling process. Therefore, optimizing the milling process, including correctly selecting grinding media, is essential to reduce energy consumption. This article presents experimental studies of the grinding process of a model material (quartz sand) in a laboratory vibratory mill. Five sets of grinding media with different diameters were used in the research, and grinding was conducted for various durations. The studies showed that the vibratory grinding process is efficient for each set of grinding media and grinding durations. The research has shown that conducting studies on the proper selection of mills is beneficial, especially regarding very fine grinding of various materials. The study confirmed that properly selecting grinding media sets can significantly accelerate the grinding process. For the selected technological variant, it was demonstrated that using 15 mm grinding media, compared to 12 mm, resulted in a 22.5% reduction in grinding time to achieve a specified particle size class of 0-10 µm.

4.
Insect Sci ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38747084

RESUMO

Distressed western carpenter ants, Camponotus modoc, produce alarm pheromone and substrate-borne vibrations. The alarm pheromone attracts nestmates but the effects of vibratory signals, or of bimodal pheromonal and vibratory signals, are not known. Worker ants of two Camponotus congeners reportedly stand still ("freeze") or run fast in response to engineered drumming vibrations inputted on plastic, but many responses to ant-produced vibratory signals on wood have not yet been investigated. Generally, orientating toward signalers under vertebrate predator attack seems maladaptive and not beneficial to ant colonies. We tested the hypotheses (1) that vibratory alarm signals cause freezing, rapid running but not attraction of nestmates, and (2) that bimodal alarm signals modulate responses to monomodal alarm signals, thereby possibly reducing predation risk. Laser Doppler vibrometry recordings revealed that the ants' vibratory signals readily propagate through ant nest lamellae, and thus quickly inform nest mates of perceived threats. With a speaker modified to record and deliver vibratory signals, we obtained drumming signals of distressed ants on a Douglas fir veneer, and bioassayed signal effects on ants in an arena with a suspended veneer floor. In response playback of vibratory signals, ants ran rapidly, or froze, but did not approach the vibratory signals. Exposed to alarm pheromone, ants frequently visited the pheromone source. However, concurrently exposed to both alarm pheromone and vibratory signals, ants visited the pheromone source less often but spent more time "frozen." The ants' modulated responses to bimodal signals seem adaptive but the reproductive fitness benefits are still to be quantified.

5.
Materials (Basel) ; 17(10)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38793456

RESUMO

This paper presents geometric analyses of welded frames after free relaxing and vibratory stress relief (VSR). The tested frames were components of a prototype packaging machine. Two types of relaxation were carried out to remove stresses introduced as a result of the welding process. One of the frames was subjected to free relaxation, while the other one was subjected to accelerated vibration relaxation. Detection of the frame geometry changes was performed using a photogrammetric system. In addition, an evaluation of the geometry change was conducted for fifteen variants of a steel frame support. A comparative analysis of the geometric deviations of the frames after free and vibratory stress relief confirmed the assumption that the frame post vibration stress relief better reproduces the nominal dimensions. Nevertheless, it should be emphasized that after vibratory stress relief, the frame is not subject to further deformation, which is a desirable effect. In the case of free relaxing, the frame undergoes dimensional changes in a random manner. In summary, carrying out accelerated vibratory stress relief allows for control of spontaneous dimensional changes in the designed frame of a packaging machine resulting from spontaneous relaxation of stresses arising from the welding process. The shortening of the relaxation process of the welded frame is also an unquestionable advantage.

6.
Audiol Res ; 14(2): 386-400, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38666904

RESUMO

OBJECTIVE: Cochlear receptors are sensitive to vibratory stimuli. Based on this sensibility, bone-anchored hearing aids have been introduced to correct unilateral or bilateral conductive or mixed hearing loss and unilateral deafness. The vestibular system is also sensitive to the vibratory stimulus and this type of response is used in clinics to test its functionality. Being aware of this double separated sensibility, we wondered whether bone vibration, which activates the acoustic receptors of patients with bone conduction aids, can also influence the functionality of the vestibular system. METHODS: To this end, we recruited 12 patients with a bone-anchored hearing aid and evaluated their vestibular function with and without an activated vibratory acoustic device. RESULTS: Our results show that the vibratory stimulus delivered by the bone conduction aid also reaches and stimulates the vestibular receptors; this stimulation is evidenced by the appearance or modification of some nystagmus findings during bedside vestibular testing. Despite this, none of these patients complained of dizziness or vertigo during prosthesis use. Nystagmus that appeared or changed during acoustic vibratory stimulation through the prosthesis was almost all predominantly horizontal, unidirectional with respect to gaze or body position, inhibited by fixation, and most often consistent with vestibular function tests indicating peripheral vestibular damage. CONCLUSIONS: The findings of sound-evoked nystagmus seem to indicate peripheral rather than central vestibular activation. The occurrence of some predominantly horizontal and high-frequency induced nystagmus seems to attribute the response mainly to the utricle and lateral semicircular canal.

7.
Bioengineering (Basel) ; 11(3)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38534560

RESUMO

Focal vibratory stimulation (FVS) and neuromuscular electrical stimulation (NMES) are promising technologies for sensory rehabilitation after stroke. However, the differences between these techniques in immediate neuromodulatory effects on the poststroke cortex are not yet fully understood. In this research, cortical responses in persons with chronic stroke (n = 15) and unimpaired controls (n = 15) were measured by whole-brain electroencephalography (EEG) when FVS and NMES at different intensities were applied transcutaneously to the forearm muscles. Both FVS and sensory-level NMES induced alpha and beta oscillations in the sensorimotor cortex after stroke, significantly exceeding baseline levels (p < 0.05). These oscillations exhibited bilateral sensory deficiency, early adaptation, and contralesional compensation compared to the control group. FVS resulted in a significantly faster P300 response (p < 0.05) and higher theta oscillation (p < 0.05) compared to NMES. The beta desynchronization over the contralesional frontal-parietal area remained during NMES (p > 0.05), but it was significantly weakened during FVS (p < 0.05) after stroke. The results indicated that both FVS and NMES effectively activated the sensorimotor cortex after stroke. However, FVS was particularly effective in eliciting transient involuntary attention, while NMES primarily fostered the cortical responses of the targeted muscles in the contralesional motor cortex.

8.
Cureus ; 16(2): e53936, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38469017

RESUMO

There are various reports describing physiotherapy rehabilitation in Guillain-Barré syndrome (GBS) but the use of current to rehabilitate GBS patients has remained an untouched topic. To elaborate on this work, we describe a case report focusing on the intervention plan for the rehabilitation of a chronic GBS case by the use of vibratory motor stimulation (VMS) current. The study aimed to describe the therapeutic application of VMS current in improving muscle power of dorsiflexors and overall outcome measures in a case of GBS presenting in a tertiary care hospital in North India. A 29-year-old male patient came to Teerthanker Mahaveer University Hospital and consulted in the Department of Physiotherapy after 1.4 years of being diagnosed with acute motor axonal neuropathy-type GBS. Rehabilitation of this case included strengthening exercises of the upper and lower limbs along with balance exercises. Specifically, in this case, we gave VMS current after assessing the muscle power of the dorsiflexors, which was found to be grade-0 over the bilateral dorsiflexors, combined with passive dorsiflexion. Different outcome measures were used for assessment, including manual muscle testing, functional independence measurement, and the Berg Balance Scale. Improvement in the patient's condition was observed in his outcome measures after two months of treatment. There was an overall improvement in the muscle power of our patient's dorsiflexors, where muscle power was upgraded from grade-0 to grade-I and grade-I+ in the bilateral lower limbs by the use of VMS current. This study marks a novel application of VMS to the dorsiflexors of a GBS patient, yielding positive outcomes in upgrading muscle power grades from grade-0 to grade-I and grade-I+. Further research is needed to confirm VMS efficacy as an early intervention in GBS patient rehabilitation.

10.
Fertil Steril ; 121(3): 545-547, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368076

RESUMO

OBJECTIVES: To demonstrate the different techniques used to perform successful penile vibratory stimulation (PVS) to induce ejaculation in men with spinal cord injuries (SCIs). DESIGN: A video demonstration of the PVS procedure performed in men with SCIs using the FertiCare 2.0 medical vibrator. SETTING: Major University Medical Center. PATIENTS: Men with SCIs. INTERVENTION(S): Spinal cord injury is the leading cause of anejaculation in young men. After SCIs, most of these men will need a method of assisted ejaculation to achieve biological fatherhood. In this study, a newly designed and tested vibrator (FertiCare 2.0) was used to induce ejaculation. The initial assessment of each patient included a standard history, physical examination, level of injury determination using the International Standards for Neurological Classification of Spinal Cord Injury as well as assessment of the hip flexor reflex and the bulbocavernosus reflex. Patients with a level of injury at or rostral to T6 were pretreated with 10-40 mg of sublingual nifedipine to manage autonomic dysreflexia. A single vibrator was applied to the dorsum, or frenulum, of the glans penis. Stimulation is delivered in 2-minute increments to a maximum of 10 minutes per visit. Application of two vibrators or abdominal electrical stimulation concurrently with PVS was used in select patients. Ejaculated semen was collected in a sterile cup and examined after liquefaction. Bladder preparation using sperm wash medium was performed in patients suspected of experiencing retrograde ejaculation. MAIN OUTCOME MEASURE(S): Successful ejaculation after performing the PVS procedure in men with SCIs. RESULTS: Penile vibratory stimulation was successful in 86% of men whose level of injury was T10 or rostral. The total motile sperm count in antegrade ejaculates produced using PVS was >5 million (lower limit considered for intrauterine insemination) in 71% of ejaculates. No complications because of PVS were observed in 3,700 trials performed by our group and none in the patients presented in this video. CONCLUSION(S): Penile vibratory stimulation is a safe and effective method for the management of ejaculatory dysfunction in men with SCIs. Penile vibratory stimulation can be performed by the male partner after an initial evaluation by a specialized provider, and the ejaculate can be used to perform home insemination.


Assuntos
Disfunção Ejaculatória , Infertilidade Masculina , Traumatismos da Medula Espinal , Humanos , Masculino , Sêmen , Pênis , Ejaculação/fisiologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico , Traumatismos da Medula Espinal/terapia , Vibração/uso terapêutico
11.
Sci Rep ; 14(1): 5026, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424248

RESUMO

In this article, an engineering problem of three co-rotating exciters with the circular distribution in a vibrating system is investigated. The dynamical model constructed by the motion differential equations is established. By introducing the small parameter averaged method in the dynamic equation, the synchronization and stability conditions of the electromechanical coupling dynamical model is derived. To illustrate the necessity of the controlling method, the self-synchronization of the vibrating system is firstly analyzed with the theory, numerical simulations and experiments. With the self-synchronization results, it is indicated that the ellipse trajectory which is needed in the industry can't be realizefd by the self-synchronization motion of the vibrating system. And then, a fuzzy PID controlling method based on the master-slave controlling strategy is introduced in the vibrating system to realize the controlled synchronization. The Lyapunov stability criterion is given to certify the stability of the controlling system. Through some simulations and experiments, the effectiveness of controlled synchronization is illustrated in the discussion. Finally, the present work illuminates the feasibility and practicality for designing some new types of vibrating screens in the industry.

12.
J Econ Entomol ; 117(1): 240-250, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38071646

RESUMO

Liriomyza chinensis (Kato) is a formidable pest of Allium species, especially the Japanese bunching onion Allium fistulosum L. Recently, a novel biotype of L. chinensis (biotype B) has emerged, which causes more severe damage than the native biotype A. It has been reported that biotype B has frequently displaced biotype A in the Japanese bunching onion fields in Japan. As interbiotype hybridization is a possible factor that influences such displacement, interbiotype hybridization was conducted between L. chinensis biotypes A and B. Eggs were not laid under one-by-one crossing conditions; however, adult hybrid progeny of both sexes emerged from no-choice mating combinations-when multiple males and females were present. The fertility of F1 hybrid adults was also investigated, and backcrossed adults emerged from F1 females in both mating combinations. F1 males might have exhibited reproductive abnormalities because only a small number of backcross progeny emerged from the mating combinations using F1 males. Additionally, 3 representative endosymbionts (Wolbachia, Spiroplasma, and Cardinium) were investigated, and both biotypes were found to be infected by the same strain of Wolbachia. In addition, the courtship signals (tapping) of male adults differed between biotypes A and B as well as between F1 hybrids; the F1 males exhibited tapping behavior that was intermediate between biotypes A and B. Therefore, mating sounds serve as a form of premating reproductive isolation between biotypes A and B.


Assuntos
Dípteros , Hemípteros , Feminino , Masculino , Animais , Dípteros/genética , Reprodução , Hibridização Genética , Fertilidade
13.
Materials (Basel) ; 16(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38068171

RESUMO

This paper presents the research results on the influence of vibration abrasive machining parameters on the surface layer integrity of elements made by LPBF technology from Inconel 939. The research was carried out on samples of various sizes on vibrating smoothing machines. The influence of the size of the processed elements, the type of abrasive shapes, the processing time, and the supporting fluid on the surface roughness and microstructure of the processed elements was analyzed. Tests have shown that as a result of using vibration processing, it is possible to reduce the surface roughness five times to the value of Ra = 1.1 µm. A significant influence of the type of abrasive shapes was found. There was no significant effect of the machining fluid on the process.

14.
Proc Biol Sci ; 290(2013): 20231910, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38113943

RESUMO

Emitting conspicuous signals into the environment to attract mates comes with the increased risk of interception by eavesdropping enemies. As a defence, a commonly described strategy is for signallers to group together in leks, diluting each individual's risk. Lekking systems are often highly social settings in which competing males dynamically alter their signalling behaviour to attract mates. Thus, signalling at the lek requires navigating fluctuations in risk, competition and reproductive opportunities. Here, we investigate how behavioural defence strategies directed at an eavesdropping enemy have cascading effects across the communication network. We investigated these behaviours in the túngara frog (Engystomops pustulosus), examining how a calling male's swatting defence directed at frog-biting midges indirectly affects the calling behaviour of his rival. We found that the rival responds to swat-induced water ripples by increasing his call rate and complexity. Then, performing phonotaxis experiments, we found that eavesdropping fringe-lipped bats (Trachops cirrhosus) do not exhibit a preference for a swatting male compared to his rival, but females strongly prefer the rival male. Defences to minimize attacks from eavesdroppers thus shift the mate competition landscape in favour of rival males. By modulating the attractiveness of signalling prey to female receivers, we posit that eavesdropping micropredators likely have an unappreciated impact on the ecology and evolution of sexual communication systems.


Assuntos
Quirópteros , Vocalização Animal , Animais , Masculino , Feminino , Comportamento Predatório , Anuros , Comportamento Sexual Animal , Reprodução
15.
Front Physiol ; 14: 1202613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38028790

RESUMO

Introduction: The aging process is associated with changes in body composition, including fat gain and skeletal muscle loss from middle age onward. Moreover, increased risk of functional decline and the development of chronic diseases are also related to aging. Objective: This systematic review and meta-analysis aimed to evaluate the effects of whole-body vibration exercise (WBVE), as a physical exercise, on body composition in people over 60 years of age. Methods: Searches were performed on PubMed, Scopus, Web of Science, and Embase. Only randomized clinical trials evaluating the effects of WBVE on body composition in older individuals were considered. The methodological quality of the studies involved was assessed using the Physiotherapy Evidence Database (PEDro) scale, recommendations from the Cochrane Collaboration were used to assess risk of bias, and quality of evidence was assessed using the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology. RevMan 5.4 was used to calculate standardized mean differences and confidence intervals of 95% (CIs). Results: Eight studies were included in this review with a mean methodological quality score of 7.5, which is considered high quality on the PEDro scale. The included studies suggest that more robust research with protocols and well-designed comparison groups is required to better assess changes in the body composition of older individuals through WBVE. Quantitative results were calculated, with differences in weighted means, differences in standardized means, and 95% confidence intervals (CIs). Conclusion: WBVE evaluated by the studies included in this review did not demonstrate improvements in body composition, and no significant effect of WBVE was found on fat mass with standardized differences (SD = -1.92; 95% CI: -4.81 to -0.98; p = 0.19), lean mass with standardized mean differences (SMD = 0.06 CI 95% [-0.21; -0.33]; p = 0.67), or skeletal muscle mass with standardized differences (SD = 0.10; CI 95% [-1.62; 1.83]; p = 0.91). Therefore, to date, there is lack of adequate evidence to state that WBVE can benefit the body composition of men and women over 60 years of age. However, further studies are required to better understand the physiological impacts of WBVE on body composition. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/#myprosperoCRD42021248871, identifier CRD42021248871.

16.
Int J Neurosci ; : 1-8, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37878354

RESUMO

BACKGROUND: The recovery of autonomic functions and the ability to reproduce in particular is of the highest priority to individuals with spinal cord injury (SCI). The potential of epidural spinal cord stimulation (ESCS) for promoting recovery of sensorimotor functions in the chronic phase of SCI has long been studied. In recent years, several studies have emerged confirming the positive effect of ESCS also on the cardiovascular system and neurogenic bladder and bowel. However, the potential of ESCS in restoring sexual function, especially ejaculation, has not yet been addressed. CASE REPORT: Two cases of people with chronic sensorimotor complete SCI in the 4th thoracic spinal segment are presented. Both men were also diagnosed with severe erectile dysfunction and anejaculation. Thanks to ESCS, Participant 1 successfully restored the ejaculatory reflex using PVS in his home environment. His outcome was subsequently verified under clinical conditions. During ESCS, Participant 1 was also able to achieve ejaculation by masturbation; moreover, he conceived a child naturally without the need for IVF. In Participant 2, we then demonstrated the same effect of ESCS on the restoration of the ejaculatory reflex when targeting the stimulation to the same spinal segment. CONCLUSION: This is the first report on the potential of ESCS for restoring the ability to ejaculate in individuals with complete SCI. Confirmation of these results could significantly reduce the need for assisted reproduction and improve the quality of life of men after SCI in the future.

17.
Materials (Basel) ; 16(17)2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37687512

RESUMO

The article reports the results of experimental study of vibratory surface grinding in the range of low excitation frequencies and variable directions of excited vibrations in the plane of the table, and investigates the effect of these directions on the roughness and waviness of the ground surface. The tests were conducted on a production surface grinder with a vibrating table on which the samples were mounted. The table made it possible to change the direction for the introduction of vibrations to the workpiece (longitudinally, transversely, and obliquely to the longitudinal feed of the table) and the parameters of the introduced vibrations, frequency and amplitude. In the course of the study, selected parameters of surface roughness and waviness of samples ground conventionally and with vibrations introduced on the workpiece were compared. The results show an improvement in the roughness and waviness parameters of the vibration-ground surfaces compared to surfaces ground without vibration (conventionally). The profile of the ground surface was subjected to Fourier analysis and the harmonic components of the surface shape of the ground samples were determined to characterize the effect of the introduced vibrations on the surface roughness. It was determined that the direction of vibration introduction, which is most favorable in terms of the parameters of the geometric structure of the ground surface, is the direction perpendicular to the longitudinal feed of the grinding table. In other directions of vibration introduction, the simultaneous effect of improving both parameters of the geometric structure of the ground surface profile was not obtained.

18.
J Voice ; 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37739862

RESUMO

OBJECTIVE: The vibratory source for voicing in children with dysphonia is classified into three categories including a glottal vibratory source (GVS) observed in those with vocal lesions or hyperfunction; supraglottal vibratory sources (SGVS) observed secondary to laryngeal airway injuries, malformations, or reconstruction surgeries; and a combination of both glottal and supraglottal vibratory sources called mixed vibratory source (MVS). This study evaluated the effects of vibratory source on three primary dimensions of voice quality (breathiness, roughness, and strain) in children with GVS, SGVS, and MVS using single-variable matching tasks and computational measures obtained from bio-inspired auditory models. METHODS: A total of 44 dysphonic voice samples from children aged 4-11 years were selected. Seven listeners rated breathiness, roughness, and strain of 1000-ms /ɑ/ samples using single-variable matching tasks. Computational estimates of pitch strength, amplitude modulation filterbank output, and sharpness were obtained through custom-designed MATLAB algorithms. RESULTS: Perceived roughness and strain were significantly higher in children with SGVS and MVS compared to children with GVS. Among the computational measures, only the modulation filterbank output resulted in significant differences among vibratory sources; a posthoc test revealed that children with SGVS had greater amplitude modulation than children with GVS, as expected from their rougher voice quality. CONCLUSIONS: The results indicate that the output of an auditory amplitude modulation filterbank model may capture characteristics of SGVS that are strongly related to the rough voice quality.

19.
Healthcare (Basel) ; 11(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37628441

RESUMO

Declining proprioceptive function is associated with problems such as lower back pain and falls. Therefore, we developed a vibration device using sweep frequency to evaluate several proprioceptors with different response frequency ranges. This study aimed to elucidate the biological responses of healthy individuals to vibratory stimulation at different sites and frequency ranges and to propose cutoff values to determine the decline in proprioceptive function. Mechanical vibration was separately applied to the lower legs and lower back, and proprioceptive function was evaluated by defining the ratio of the center of pressure (CoP) in the anteroposterior direction during mechanical vibration to that during no vibration in the three frequency ranges. The cut-off value was defined as the mean value, with the standard deviation subtracted for each indicator. The cut-off values were higher in the lower legs than in the lower back at all frequency ranges and in the 30-53 Hz and 56-100 Hz frequency ranges for both the lower legs and lower back. In healthy individuals, 9.9% and 8.6% were below the cut-off values in the 30-53 Hz and 56-100 Hz frequency ranges for the lower legs, respectively.

20.
Materials (Basel) ; 16(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37445075

RESUMO

The endurance limit of structural mechanical components is affected by the residual stress state, which depends strongly on the manufacturing process. In general, compressive residual stresses tend to result in an increased fatigue strength. Post-manufacturing processes such as shot peening or vibratory finishing may achieve such a compressive residual stress state. But within complex components, manufacturing-process-based imperfections severely limit the fatigue strength. Thus, the interactions of imperfections, residual stress state and material strength are key aspects in fatigue design. In this work, cast steel and aluminium alloys are investigated, each of them in vibratory finished and polished surface condition. A layer-based fatigue assessment concept is extended towards stable effective mean stress state considering the elastic-plastic material behaviour. Murakami's concept was applied to incorporate the effect of hardness change and residual stress state. Residual stress relaxation is determined by elastic-plastic simulations invoking a combined hardening model. If the effective stress ratio within the local layer-based fatigue strength is evaluated as critical distance value, a sound calculation of fatigue strength can be achieved. Summing up, the layer-based fatigue strength design is extended and features an enhanced understanding of the effective stabilized mean stress state during cyclic loading.

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