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1.
Molecules ; 29(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38999086

RESUMO

Orthoconic antiferroelectric liquid crystals (OAFLCs) represent unique self-organized materials with significant potential for applications in photonic devices due to their sub-microsecond switching times and high optical contrast in electro-optical effects. However, almost all known OALFCs suffer from low chemical stability and short helical pitch values. This paper presents the synthesis and study results of two chiral AFLCs, featuring a four-ring structure in the rigid core and high chemical stability. The mesomorphic properties of these compounds were investigated using polarizing optical microscopy and differential scanning calorimetry. Spectrometry and electro-optical studies were employed to estimate the helical pitch, tilt angle, and spontaneous polarization of the synthesized compounds and the prepared mixtures. All studied compounds exhibit enantiotropic chiral smectic mesophases including the SmA*, the SmC*, and a very broad temperature range of the SmCA* phase. Doping top-modern antiferroelectric mixture with synthesized compounds offers benefits such as increased helical pitch and tilt angle values without significantly influencing spontaneous polarization. This allows the prepared mixture to be regarded as an OAFLC with high optical contrast, characterized by an almost perfect dark state. These valuable physicochemical and optical properties suggest significant potential of studied materials for practical applications.

2.
Int Arch Otorhinolaryngol ; 28(3): e415-e423, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38974630

RESUMO

Introduction When cases of idiopathic sudden sensorineural hearing loss (SSNHL) are treated successfully, most clinicians assume the normality and symmetry of the auditory processing. This assumption is based on the recovery of the detection ability on the part of the patients, but the auditory processing involves much more than detection alone. Since certain studies have suggested a possible involvement of the central auditory system during the acute phase of sudden hearing loss, the present study hypothesized that auditory processing would be asymmetric in people who have experienced sudden hearing loss. Objective To assess the physiologic and electrophysiological conditions of the cochlea and central auditory system, as well as behavioral discrimination, of three primary aspects of sound (intensity, frequency, and time) in subjects with normal ears and ears treated successfully for SSNHL. Methods The study included 19 SSNHL patients whose normal and treated ears were assessed for otoacoustic emissions, speech auditory brainstem response, intensity and pitch discrimination, and temporal resolution in a within-subject design. Results The otoacoustic emissions were poorer in the treated ears compared to the normal ears. Ear- and sex-dependent differences were observed regarding otoacoustic emissions and pitch discrimination. Conclusion The asymmetrical processing observed in the present study was not consistent with the hearing threshold values, which might suggest that the central auditory system would be affected regardless of the status of the peripheral hearing. Further experiments with larger samples, different recovery scenarios after treatment, and other assessments are required.

3.
Heliyon ; 10(12): e32819, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38975110

RESUMO

Purpose: To evaluate the performance of calcium quantification on photon-counting detector CT (PCD-CT) with high-pitch at low radiation doses compared to third-generation dual-source energy-integrating detector CT (EID-CT). Materials and methods: The phantom with three calcium inserts (50, 100, and 300 mg of calcium per milliliter), with and without the elliptical outer layer, was evaluated using high-pitch (3.2) and standard pitch (0.8) on PCD-CT, and standard pitch on EID-CT. Scans were performed with different tube voltages (PCD-CT: 120 and 140 kilo-voltage peak [kVp]; EID-CT: 70/Sn150 and 100/Sn150 kVp) and four radiation doses (1, 3, 5, and, 10 milli-Gray [mGy]). Utilizing the true calcium concentrations (CCtrue) of the phantom as the gold standard references, regression equations for each kVp setting were formulated to convert CT attenuations (CaCT) into measured calcium concentrations (CCm). The correlation analysis between CaCT and CCtrue was performed. The percentage absolute bias (PAB) was calculated from the differences between CCm and CCtrue and used to analyze the effects of scanning parameters on calcium quantification accuracy. Results: A strong correlation was found between CaCT and CCtrue on PCD-CT (r > 0.99) and EID-CT (r > 0.98). For high- and standard-pitch scans on PCD-CT, the accuracy of calcium quantification is comparable (p = 0.615): the median (interquartile range [IQR]) of PAB was 5.59% (2.79%-8.31%) and 4.87 % (2.62%-8.01%), respectively. The PAB median (IQR) was 7.43% (3.77%-11.75%) for EID-CT. The calcium quantification accuracy of PCD-CT is superior to EID-CT at the large phantom (5.46% [2.68%-9.55%] versus 9.01% [6.22%-12.74%]), and at the radiation dose of 1 mGy (4.43% [2.08%-8.59%] versus 13.89% [8.93%-23.09%]) and 3 mGy (4.61% [2.75%-6.51%] versus 9.97% [5.17%-14.41%]), all p < 0.001. Conclusions: Calcium quantification using low-dose PCD-CT with high-pitch scanning is feasible and accurate, and superior to EID-CT.

4.
Eur J Radiol ; 178: 111604, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38996738

RESUMO

PURPOSE: In planning transcatheter aortic valve replacement (TAVR), retrospective cardiac spiral-CT is recommended to measure aortic annulus with subsequent CT-angiography (CTA) to evaluate access routes. Photon-counting detector (PCD)-CT enables to assess the aortic annulus in desired cardiac phases, using prospective ECG-gated high-pitch CTA. The aim of this study was to evaluate the measurement accuracy of aortic annulus using prospective ECG-gated high-pitch CTA against retrospective spiral-CT reference. METHOD: Thirty patients underwent cardiac spiral-CT and prospective ECG-gated (30% R-R on aortic valve level) high-pitch CTA. Using propensity score matching, another 30 patients were identified whose CTA was performed using high-pitch mode without ECG-synchronization. Two investigators measured annular diameter, perimeter, and area on cardiac spiral-CT and high-pitch CTA. RESULTS: The aortic valve was imaged in systole in 90 % of prospective ECG-gated CTA cases but only 50 % of non-ECG-gated CTA cases (p = 0.002). There was a strong correlation (r ≥ 0.94) without significant differences (p ≥ 0.09) between cardiac spiral-CT and prospective ECG-gated high-pitch CTA for all annulus measurements. In contrast, significant differences were found in annular short-axis diameter and area between cardiac spiral-CT and non-ECG-gated high-pitch CTA (p ≤ 0.03). Furthermore, prospective ECG-gated high-pitch CTA showed significantly reduced radiation exposure compared with cardiac spiral-CT (CTDI 4.52 vs. 24.10 mGy; p < 0.001). CONCLUSION: PCD-CT-based prospective ECG-gated high-pitch scans with targeted systolic acquisition at the level of the aortic valve can simultaneously visualize TAVR access routes and accurately measure systolic annulus size. This approach could aid in optimizing protocols to achieve lower radiation doses in the growing population of younger, low-risk TAVR patients.

5.
Phys Sportsmed ; : 1-6, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39015044

RESUMO

OBJECTIVE: Developing softball pitchers are prone to injury due to the repetitive throwing motion. Many children and parents use the internet as a source of medical advice, but this information may not always be aligned with medical guidelines. The purpose of this study was to assess the medical advisability of injury prevention guidelines for developing softball pitchers on websites using Google as the primary search engine. METHODS: The first 100 websites populated from a Google search using the term softball youth pitching recommendations were evaluated. Each website was categorized as discussing baseball, softball, or both, and as athletic, commercial, or educational. For every website, 16 recommendations described by the American Orthopaedic Society for Sports Medicine (AOSSM) Stop Sports Injuries softball injury prevention guidelines (Table 1) were scored as in agreement (+1), different guideline mentioned (0.5), no mention (0), or discordant (-1).[Table: see text]. RESULTS: Of the 98 qualifying websites, 57 advised only about softball, while 19 advised about both baseball and softball. Fifty websites had no mention of any recommendation outlined by AOSSM. Websites that were mostly in agreement with AOSSM were educational websites (mean score = 3.9, p = 0.02), websites discussing only softball (mean score = 2.0, p = 0.02), and the first 50 websites (mean score = 2.2, p = 0.04). The most common discordant guideline was differing opinions in pitch count (13 websites). CONCLUSION: The most common category in disagreement with AOSSM was different pitch count guidelines, highlighting a need for websites to provide more consistent information using high-quality resources. Educational websites, websites discussing only softball, and the first 50 websites had the highest scores, indicating that these types of websites are most likely to have the highest amount of medically advisable information. We recommend users conduct targeted Google searches on reliable websites for information on pitching softball recommendations to maximize the validity of Google search results.

6.
J Orthop ; 57: 133-136, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39027353

RESUMO

Introduction: Recently, star pitchers in Major League Baseball (MLB) have faced devastating elbow injuries, causing some to question whether implementation of the MLB pitch clock during the 2023 season has led to a higher rate of elbow injuries among pitchers. This study aims to determine if implementation of the MLB pitch clock in the 2023 MLB season affected the injury rate in pitchers. Methods: Injury data was collected for the 2021, 2022, and 2023 MLB seasons using the fangraphs.com injury database. Incidence rate ratio was calculated to compare the injury rate for the 2023 season to the 2021 and 2022 seasons. A z-test for proportions was used to determine significance levels. Results: The 2023 season showed a decrease in the rate of the total number of injuries when compared to the 2021 (P = 0.01) and 2022 (P = 0.02) seasons. There was no statistical difference in the rate of Tommy John Surgery, Flexor Tendon Injuries, or other cause elbow injuries. Conclusion: Following implementation of the MLB pitch clock during the 2023 season, the total number of injuries decreased, but there was no change in the rate of elbow injuries in pitchers compared with the 2021 and 2022 MLB seasons. Future studies are needed to determine if the pitch clock has a longitudinal effect on injuries.

7.
Heliyon ; 10(12): e33276, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39027440

RESUMO

Pure copper is very soft, however, hardening the pure copper with most strengthening mechanisms leads to a significant reduction in electrical conductivity. Grain refinement is a better strengthening mechanism to maintain high enough electrical conductivity. Plastic deformation at room temperature followed by post-annealing is one of the best methods to achieve fine-grained metals and alloys. In this research, the high-temperature annealing behavior of cold-rolled electrolytic tough-pitch (ETP) copper sheets was studied. 90 % asymmetric cold rolling followed by high-temperature post-annealing at 673 K for 1, 2, 5, 10, 30, 60, and 120 min were applied on the copper. The microstructure was significantly changed with increasing annealing time from 1 to 2 min owing to full recrystallization. With increasing the annealing duration, the grain size is increased. The formation of equiaxed grains with a smaller size (∼9 µm) compared to the full-annealed (initial) sample (∼68 µm) is observed after the longest time of post-annealing (120 min) due to the pinning effect of Cu2O particles. The post-annealed copper sheets processed by asymmetric rolling (in this work) exhibited a more homogeneous microstructure through the thickness compared to the symmetric rolling due to more uniform stored strain energy. The results showed that the first deformed grains that undergo recrystallization during post-annealing are Goss-oriented grains. With an increase in the post-annealing time, the S and Copper components were eliminated and a strong Cube and P texture orientations were formed. Interestingly, after 1 min of post-annealing, the yield and tensile strength enhanced to 410.2 MPa and 418.6 MPa owing to the annealing hardening phenomenon. The hardness and strength reached a constant value after the post-annealing for 10 min and above. With increasing the post-annealing duration, the central area of fracture surfaces (consisting of ductile dimples) became larger and the outer region (consisting of flat surfaces and shear dimples) became smaller, showing a shift towards perfect ductile fracture. With the increase of post-annealing time from 1 min to 120 min, the electrical conductivity was increased from 77.6 to 97.5 %IACS. The presence of the Cube texture increased the electron mobility compared to the P orientation, by reducing the mean distance that they can travel without scatter. From the obtained results, it can be concluded that the asymmetric cold rolling followed by high-temperature post-annealing is capable of strength improvement and maintaining electrical conductivity in copper.

8.
Neuropsychologia ; : 108960, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39032629

RESUMO

Congenital amusia is a neurodevelopmental disorder characterized by deficits of music perception and production, which are related to altered pitch processing. The present study used a wide variety of tasks to test potential patterns of processing impairment in individuals with congenital amusia (N=18) in comparison to matched controls (N=19), notably classical pitch processing tests (i.e., pitch change detection, pitch direction of change identification, and pitch short-term memory tasks) together with tasks assessing other aspects of pitch-related auditory cognition, such as emotion recognition in speech, sound segregation in tone sequences, and speech-in-noise perception. Additional behavioral measures were also collected, including text reading/copying tests, visual control tasks, and a subjective assessment of hearing abilities. As expected, amusics' performance was impaired for the three pitch-specific tasks compared to controls. This deficit of pitch perception had a self-perceived impact on amusics' quality of hearing. Moreover, participants with amusia were impaired in emotion recognition in vowels compared to controls, but no group difference was observed for emotion recognition in sentences, replicating previous data. Despite pitch processing deficits, participants with amusia did not differ from controls in sound segregation and speech-in-noise perception. Text reading and visual control tests did not reveal any impairments in participants with amusia compared to controls. However, the copying test revealed more numerous eye-movements and a smaller memory span. These results allow us to refine the pattern of pitch processing and memory deficits in congenital amusia, thus contributing further to understand pitch-related auditory cognition. Together with previous reports suggesting a comorbidity between congenital amusia and dyslexia, the findings call for further investigation of language-related abilities in this disorder even in the absence of neurodevelopmental language disorder diagnosis.

9.
Chemistry ; : e202400189, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958147

RESUMO

Because of its high specific capacity and superior rate performance, porous carbon is regarded as a potential anode material for lithium-ion batteries (LIBs). However, porous carbon materials with wide pore diameter distributions suffer from low structural stability and low electrical conductivity during the application process. During this study, the calcium carbonate nanoparticle template method is used to prepare coal tar pitch-derived porous carbon (CTP-X). The coal tar pitch-derived porous carbon has a well-developed macroporous-mesoporous-microporous hierarchical porous network structure, which provides abundant active sites for Li+ storage, significantly reduces polarization and charge transfer resistance, shortens the diffusion path and promotes the rapid transport of Li+. More specifically, the CTP-2 anode shows high charge capacity (496.9 mAh g-1 at 50 mA g-1), excellent rate performance (413.6 mAh g-1 even at 500 mA g-1), and high cycling stability (capacity retention rate of about 100% after 1,000 cycles at 2 A g-1). The clean and eco-friendly large-scale utilization of coal tar pitch will facilitate the development of high-performance anodes in the field of LIBs.

10.
Elife ; 132024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963785

RESUMO

Intonation in speech is the control of vocal pitch to layer expressive meaning to communication, like increasing pitch to indicate a question. Also, stereotyped patterns of pitch are used to create distinct sounds with different denotations, like in tonal languages and, perhaps, the 10 sounds in the murine lexicon. A basic tone is created by exhalation through a constricted laryngeal voice box, and it is thought that more complex utterances are produced solely by dynamic changes in laryngeal tension. But perhaps, the shifting pitch also results from altering the swiftness of exhalation. Consistent with the latter model, we describe that intonation in most vocalization types follows deviations in exhalation that appear to be generated by the re-activation of the cardinal breathing muscle for inspiration. We also show that the brainstem vocalization central pattern generator, the iRO, can create this breath pattern. Consequently, ectopic activation of the iRO not only induces phonation, but also the pitch patterns that compose most of the vocalizations in the murine lexicon. These results reveal a novel brainstem mechanism for intonation.


Assuntos
Vocalização Animal , Animais , Vocalização Animal/fisiologia , Camundongos , Tronco Encefálico/fisiologia , Respiração , Fonação/fisiologia
11.
J Affect Disord ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038622

RESUMO

BACKGROUND: Individuals with high social interaction anxiety (SIA) and depression often behave submissively in social settings. Few studies have simultaneously examined the associations between objectively assessed submissive behaviors and SIA or depression, despite their high comorbidity and unknown mechanisms regarding submissiveness. METHODS: A sample of 45 young adults self-reported trait SIA and depression, state positive/negative affect (PA/NA) before and after a virtual social interaction. Participants engaged in a four-minute conversation with a confederate who was trained to behave neutrally. Mutual eye gaze, via eye-tracking, and vocal pitch were assessed throughout the interaction. RESULTS: Depression and SIA were positively correlated with NA, poorer self-rated performance, and vocal pitch. Highly socially anxious women engaged in less mutual eye gaze than highly socially anxious men. Also, vocal pitch was inversely associated with mutual eye gaze and positively related to NA and (nonsignificantly) to self-ratings of poor performance. Finally, our data partially replicated past research on the use of vocal pitch during social stress to detect social anxiety disorder. LIMITATIONS: The current sample is relatively homogenous in educational attainment, age, and race. All research confederates were women. Future research should examine whether these archival data replicate with the latest telecommunication technologies. CONCLUSION: Our findings highlight nuanced relationships among SIA, depression, emotions, self-perceptions, and biobehavioral indicators of submissive behavior-in response to an ambiguously negative/positive social interaction. Sex/gender may interact with these effects, emphasizing considerations for research method designs.

12.
Nanotechnology ; 35(38)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38906124

RESUMO

A variety of strategies have been developed to enhance the cycling stability of Si-based anodes in lithium-ion batteries. Although significant progress has been made in enhancing the cycling stability of Si-based anodes, the low initial Coulombic efficiency (ICE) remains a significant challenge to their commercial application. Herein, pitch-based carbon (C) coated Si nanoparticles (NPs) were wrapped by graphene (G) to obtain Si@C/G composite with a small specific surface area of 11.3 m2g-1, resulting in a high ICE of 91.2% at 500 mA g-1. Moreover, the integrated utilization of graphene and soft carbon derived from the low-cost petroleum pitch strongly promotes the electrical conductivity, structure stability, and reaction kinetics of Si NPs. Consequently, the synthesized Si@C/G with a Si loading of 54.7% delivers large reversible capacity (1191 mAh g-1at 500 mA g-1), long cycle life over 200 cycles (a capacity retention of 87.1%), and superior rate capability (952 mAh g-1at 1500 mA g-1). When coupled with a homemade LiNi0.8Co0.1Mn0.1O2(NCM811) cathode in a full cell, it exhibits a promising cycling stability for 200 cycles. This work presents an innovative approach for the manufacture of Si-based anode materials with commercial application.

13.
Cell Tissue Bank ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869670

RESUMO

Severe burns often result in an exacerbated inflammatory response, which can contribute to further injury. This inflammatory response may lead to an increased risk of infection, multiple organ failure, and death. This study aimed to investigate the potential of reducing inflammation to enhance burn wound healing in rats using ovine's small intestinal submucosa as a carrier for Wharton's jelly mesenchymal stem cells (WJ-MSCs) and Mineral Pitch (MP). A rat burn model was developed, and the animals were divided into four groups: control group: burn, placebo group: scaffold-treated burn, cell experimental group: WJ-MSCs seeded scaffold-treated burn, and cell and MP experimental group: scaffolds loaded with WJ-MSCs and MP-treated burn. After treating the wounds in the relevant groups and sampling them on days 5, 14 and 21, histological and pathological parameters, and the expression of genes involved in angiogenesis and epithelialization were evaluated. The study results revealed several findings in the burn wounds. These included changes in mast cell populations, a decrease in inflammatory neutrophils and lymphocytes, an increase in fibroblasts and blood vessels, and upregulation of angiogenesis and epithelialization genes. These changes collectively contributed to enhanced wound healing in cell and MP experimental group compared to the other groups. The findings suggest that scaffolds loaded with Wharton's jelly-derived stem cells and MP can serve as engineered tools to modulate inflammatory conditions during the burn wound healing process. These interventions can improve burn wound management and promote better outcomes.

14.
Auris Nasus Larynx ; 51(4): 738-746, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38850719

RESUMO

OBJECTIVE: The present study aimed to observe and analyze the ocular movements induced by Coriolis stimulation (eccentric pitch while rotating: PWR) that induces Coriolis forces on the vestibular apparatus of healthy human individuals. METHODS: A total of 31 healthy subjects participated in the study. Eccentric PWR was performed on 27 subjects, by pitching the participants' heads forward and backward at an angle of 30° each on an axis parallel and 7 cm below inter-aural axis, at a frequency of 0.5 Hz while on a chair rotating at a constant angular velocity of 97.2°/s on the earth-vertical axis. Ocular movements during stimulation were recorded using three-dimensional video-oculography. As a subsidiary analysis, 0.5 Hz head roll tilt was used as another stimulus that also induced torsional ocular movements. The forces induced on the vestibular apparatus, and phases of ocular torsion against the stimulus were calculated from the observed data. RESULTS: In the Coriolis stimulation during rightward yaw rotation, a rightward ocular torsion of 4.8° on average, was observed when the head pitched forward, and the direction of ocular torsion reversed when the head pitched backward. During leftward yaw rotation, these relationships were reversed with an average amplitude of 4.7° The phase of ocular torsion preceded that of Coriolis force by 0.2 s during rightward rotation and 0.14 s during leftward rotation. There were no significant differences in amplitude or phase between the directions of rotation. The phase lead of 0.5 Hz roll-tilt was significantly smaller than that of Coriolis stimulation (p < 0.01). CONCLUSION: Coriolis stimulation induced a specific pattern of ocular torsion, where its direction and phase suggested that the mechanism likely involved both the otolith and semicircular canals. Further studies may provide a clue to the magnitude of the otolith and semicircular canal contributions.

15.
Biology (Basel) ; 13(6)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38927251

RESUMO

Auditory temporal processing is a vital component of auditory stream segregation, or the process in which complex sounds are separated and organized into perceptually meaningful objects. Temporal processing can degrade prior to hearing loss, and is suggested to be a contributing factor to difficulties with speech-in-noise perception in normal-hearing listeners. The current study tested this hypothesis in middle-aged adults-an under-investigated cohort, despite being the age group where speech-in-noise difficulties are first reported. In 76 participants, three mechanisms of temporal processing were measured: peripheral auditory nerve function using electrocochleography, subcortical encoding of periodic speech cues (i.e., fundamental frequency; F0) using the frequency following response, and binaural sensitivity to temporal fine structure (TFS) using a dichotic frequency modulation detection task. Two measures of speech-in-noise perception were administered to explore how contributions of temporal processing may be mediated by different sensory demands present in the speech perception task. This study supported the hypothesis that temporal coding deficits contribute to speech-in-noise difficulties in middle-aged listeners. Poorer speech-in-noise perception was associated with weaker subcortical F0 encoding and binaural TFS sensitivity, but in different contexts, highlighting that diverse aspects of temporal processing are differentially utilized based on speech-in-noise task characteristics.

16.
Orthop J Sports Med ; 12(6): 23259671241256294, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38895136

RESUMO

Background: Ulnar collateral ligament (UCL) injuries in youth pitchers continue to be concerning despite the institution of pitch count limits. Flexor-pronator mass fatigue can lead to diminished dynamic stability, resulting in greater stress on the UCL. Purpose/Hypothesis: To evaluate fatigue of the flexor-pronator mass by assessing changes in medial elbow laxity; noninvasively characterizing alterations in muscle glycogen; and identifying changes in subjective fatigue, strength, range of motion (ROM), pitching velocity, and accuracy with increasing pitches thrown by youth pitchers to their recommended 75-pitch count limit. It was hypothesized that, with increased pitches, medial elbow laxity would increase and that the glycogen content of the flexor-pronator mass would decrease. Study Design: Descriptive laboratory study. Methods: Healthy male pitchers aged 10 years (n = 22) threw 3 sets of 25 pitches with 12 minutes between sets (3 timepoints). Bilateral ulnohumeral joint gapping was measured by applying a standardized valgus force and utilizing ultrasound imaging. Relative changes in muscle glycogen in the bilateral flexor carpi radialis (FCR), and the flexor digitorum superficialis/flexor carpi ulnaris (FDS/FCU) muscles were measured with ultrasound software and recorded as fuel percentiles. Additional measures obtained included subjective fatigue, strength, ROM, velocity, and accuracy. Results: There were no differences in medial elbow joint-line gapping between the throwing and nonthrowing arms or between timepoints. The throwing arm demonstrated a significant decline in fuel percentile of the FCR from baseline to after 75 pitches (P = .05). There were no differences across timepoints for FDS/FCU fuel percentile values. Fatigue measurements for both arms were significantly higher at all timepoints compared with baseline (P≤ .03). Grip strength of the dominant arm after 75 pitches was decreased significantly compared with after 25 pitches (P = .02). Conclusion: Although an increase in medial elbow joint gapping was not demonstrated within the recommended 75 pitch count limit in 10-year-olds, a relative decrease in glycogen stores of the flexor-pronator mass did occur, as well as a decrease in grip strength, with increasing subjective fatigue. Clinical Relevance: This study provides a foundation for further objective testing of physiologic changes that occur with pitching to better guide pitch count limits and improve the safety of young athletes.

17.
Acta Otolaryngol ; 144(3): 226-232, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38847804

RESUMO

BACKGROUND: Clinically, we find that tinnitus patients often have hearing loss. According to the most accepted mechanism of tinnitus, that is, the spontaneous discharge and abnormal synchronization of neurons after afferent reduction, tinnitus frequency is closely related to the frequency of hearing loss. OBJECTIVE: The purpose of this study was to investigate the correlation of tinnitus pitch with the frequency of hearing loss. MATERIALS AND METHODS: A total of 500 patients with unilateral or bilateral chronic tinnitus were enrolled in this study. All patients underwent pure tone audiometry (PTA) and tinnitus acoustic examination. Hearing loss levels and frequencies were recorded. The relationship between tinnitus pitch and hearing loss level and frequency was statistically analyzed. RESULTS: Our results showed that 96.6% of the 500 tinnitus patients had hearing loss. Statistical analysis showed that low frequency (LF) tinnitus was correlated with LF hearing loss, but moderate frequency & high frequency (MF&HF) tinnitus was not significantly associated with MF&HF hearing loss. The coincidence of tinnitus pitch with the highest hearing threshold correlated with the degree of hearing loss. CONCLUSION AND SIGNIFICANCE: The vast majority of patients with chronic subjective tinnitus had hearing loss, and the frequency of tinnitus correlated with the degree and frequency of hearing loss but not exactly fall within the frequency range of hearing loss.


Assuntos
Audiometria de Tons Puros , Perda Auditiva , Zumbido , Humanos , Zumbido/epidemiologia , Zumbido/complicações , Zumbido/fisiopatologia , Masculino , Estudos Transversais , Feminino , Pessoa de Meia-Idade , Adulto , Idoso , Perda Auditiva/complicações , Perda Auditiva/epidemiologia , Adulto Jovem , Limiar Auditivo , Adolescente
18.
J Colloid Interface Sci ; 673: 657-668, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38901356

RESUMO

The orientation-guidance coupled with in-situ activation methodology is developed to synthesize the N-doped porous carbon (NPC) with well-developed porosity and high specific surface area, using coal pitch as a carbon precursor. The orientation-guidance and activation are dedicated to generating microporous and mesoporous channels, respectively. The in-situ N incorporation into the carbon skeleton is realized along with the formation of porous carbon (PC), ensuring the uniformity of N doping. As an electrode material of supercapacitor, benefiting from the robust hexagon-like building block decorated with micro-mesoporous channels and N doping, NPC electrode affords a significant improvement in capacitive energy-storage performance, achieving a specific capacitance of up to 333F g-1 at 1 A/g, which far exceeds those of PC and activated carbon. Notably, even under high mass loading of 10 mg cm-2, the NPC maintains a satisfactory capacitance of 258F g-1 at 1 A/g. When employed as the anode in Li-ion capacitor (LIC), apart from exhibiting enhanced anode behavior compared to graphite anode, NPC also delivers exceptional cyclability. Furthermore, density functional theory calculations have validated the enhanced electrical conductivity and Li storage ability contributed by N doping, providing a theoretical foundation for the observed improvements in electrochemical performance. A full LIC configured with NPC anode delivers extraordinary Ragone performance and outstanding cyclability. This work also proposes a feasible way to realize the oriented conversion of coal pitch into high-performance electrode materials for electrochemical energy-storage devices.

19.
Perception ; : 3010066241249451, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38778785

RESUMO

This study aimed to investigate the perception of loudness in response to changes in fundamental frequency (F0) in spoken sounds, as well as the influence of linguistic background on this perceptual process. The results revealed that participants perceived changes in F0 to have accompanying changes in loudness, with a trend of lower F0 sounds being perceived as louder than higher F0 sounds. This finding contrasts with previous studies on pure tones, where increases in frequency typically led to increases in loudness. Furthermore, the study examined differences between two distinct groups of participants: Chinese-speaking and English-speaking individuals. It was observed that English-speaking participants exhibited a greater sensitivity to minor intensity changes compared to Chinese-speaking participants. This discrepancy in sensitivity suggests that linguistic background may play a significant role in shaping the perception of loudness in spoken sound. The study's findings contribute to our understanding of how F0 variations are perceived in terms of loudness, and highlight the potential impact of language experience on this perceptual process.

20.
Neurocase ; 30(1): 18-28, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38734872

RESUMO

A 62-year-old musician-MM-developed amusia after a right middle-cerebral-artery infarction. Initially, MM showed melodic deficits while discriminating pitch-related differences in melodies, musical memory problems, and impaired sensitivity to tonal structures, but normal pitch discrimination and spectral resolution thresholds, and normal cognitive and language abilities. His rhythmic processing was intact when pitch variations were removed. After 3 months, MM showed a large improvement in his sensitivity to tonality, but persistent melodic deficits and a decline in perceiving the metric structure of rhythmic sequences. We also found visual cues aided melodic processing, which is novel and beneficial for future rehabilitation practice.


Assuntos
Infarto da Artéria Cerebral Média , Música , Humanos , Pessoa de Meia-Idade , Masculino , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/fisiopatologia , Transtornos da Percepção Auditiva/etiologia , Transtornos da Percepção Auditiva/fisiopatologia
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