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2.
Plant Dis ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39148367

RESUMO

Global change is exacerbating the prevalence of plant diseases caused by pathogenic fungi in forests worldwide. The conventional use of chemical fungicides, which is commonplace in agricultural settings, is not sanctioned for application in forest ecosystems, so novel control strategies are imperative. SIGS (Spray-Induced Gene Silencing) is a promising approach that can modulate the expression of target genes in eukaryotes in response to double-stranded RNA (dsRNA) present in the environment that triggers the RNA interference (RNAi) mechanism. SIGS exhibited notable success in reducing virulence when deployed against some crop fungal pathogens, such as Fusarium graminearum, Botrytis cinerea and Sclerotinia sclerotiorum, among others. However, there is a conspicuous dearth of studies evaluating the applicability of SIGS for managing forest pathogens. This research aimed to determine whether SIGS could be used to control Fusarium circinatum, a widely impactful forest pathogen that causes Pine Pitch Canker disease. Through a bacterial synthesis, we produced dsRNA molecules to target fungal essential genes involved to vesicle trafficking (Vps51, DCTN1, and SAC1), signal transduction (Pp2a, Sit4, Ppg1, and Tap42), and cell wall biogenesis (Chs1, Chs2, Chs3b, Gls1) metabolic pathways. We confirmed that F. circinatum is able to uptake externally applied dsRNA, triggering an inhibition of the pathogen's virulence. Furthermore, this study pioneers the demonstration that recurrent applications of dsRNAs in SIGS are more effective in protecting plants than single applications. Therefore, SIGS emerges as an effective and sustainable approach for managing plant pathogens, showcasing its efficacy in controlling a globally significant forest pathogen subject to quarantine measures.

3.
Orthop J Sports Med ; 12(8): 23259671241262730, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143985

RESUMO

Background: Kinematic parameters predictive of pitch velocity have been evaluated in adolescent and collegiate baseball pitchers; however, they have not been established for high school or professional pitchers. Purpose: To create multiregression models using anthropometric and kinematics features most predictive for pitch velocity in high school and professional pitchers and compare them with prior multiregression models evaluating other playing levels. Study Design: Descriptive laboratory study. Methods: High school (n = 59) and professional (n = 337) baseball pitchers threw 8 to 12 fastballs while being evaluated with 3-dimensional motion capture (480 Hz). Using anthropometric and kinematic variables, multiregression models for pitch velocity were created for each group. A systematic review was conducted to determine previous studies that established kinematic models for ball velocity in youth, high school, and collegiate pitchers. Results: Leg length was predictive of pitch velocity for high school and professional pitchers (P < .001 for both). When compared with previously established models for pitch velocity, almost all groups were distinct from one another when assessing age (P maximum < .001), weight (P max = .0095), and pitch velocity (P max < .001). Stride length was a significant predictor for the youth/high school pitchers, as well as the current study's high school and professional pitchers (P < .001 for all). Maximal shoulder external rotation (collegiate: P = .001; professional: P < .001) and maximal elbow extension velocity (high school/collegiate: P = .024; collegiate: P < .001; professional: P = .006) were shared predictors for the collegiate and current study's professional group multiregression models. Trunk flexion at ball release was a commonly shared predictor in the youth/high school (P = .04), high school/collegiate (P = .003), collegiate (P < .001), and the current study's professional group (P < .001). Conclusion: Youth, high school, collegiate, and professional pitchers had unique, predictive kinematic and anthropometric features predictive of pitch velocity. Leg length, stride length, trunk flexion at ball release, and maximal shoulder external rotation were predictive features that were shared between playing levels. Clinical Relevance: Coaches, clinicians, scouts, and pitchers can consider both the unique and the shared predictive features at each playing level when attempting to maximize pitch velocity.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39134919

RESUMO

Memory for isolated absolute pitches is extremely rare in Western, English-speaking populations. However, past research has found that people can voluntarily reproduce well-known songs in the original key much more often than chance. It is unknown whether this requires deliberate effort or if it manifests in involuntary musical imagery (INMI, or earworms). Participants (N = 30, convenience sample) were surveyed at random times over a week and asked to produce a sung recording of any music they were experiencing in their heads. We measured the "pitch error" of each recording to the nearest semitone by comparing participants' recordings to the original song. We found that 44.7% of recordings had a pitch error of 0 semitones, and 68.9% of recordings were within ± 1 semitone of the original song. Our results provide novel evidence that a large proportion of the population has access to absolute pitch, as revealed in their INMI.

5.
Phys Eng Sci Med ; 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080209

RESUMO

The stability of dosiomics features (DFs) and dose-volume histogram (DVH) parameters for detecting disparities in helical tomotherapy planned dose distributions was assessed. Treatment plans of 18 prostate patients were recalculated using the followings: field width (WF) (2.5 vs. 5), pitch factor (PF) (0.433 vs. 0.444), and modulation factor (MF) (2.5 vs. 3). From each of the eight plans per patient, ninety-three original and 744 wavelet-based DFs were extracted, using 3D-Slicer software, across six regions including: target volume (PTV), pelvic lymph nodes (PTV-LN), PTV + PTV-LN (PTV-All), one cm rind around PTV-All (PTV-Ring), rectum, and bladder. For the resulting DFs and DVH parameters, the coefficient of variation (CV) was calculated, and using hierarchical clustering, the features were classified into low/high variability. The significance of parameters on instability was analyzed by a three-way analysis of variance. All DF's were stable in PTV, PTV-LN, and PTV-Ring (average CV ( CV ¯ )  ≤ 0.36). Only one feature in the bladder ( CV ¯  = 0.9), rectum ( CV ¯  = 0.4), and PTV-All ( CV ¯  = 0.37) were considered unstable due to change in MF in the bladder and WF in the PTV-All. The value of CV ¯ for the wavelet features was much higher than that for the original features. Out of 225 unstable wavelet features, 84 features had CV ¯  ≥ 1. The CVs for all the DVHs remained very small ( CV ¯ < 0.06). This study highlights that the sensitivity of DFs to changes in tomotherapy planning parameters is influenced by the region and the DFs, particularly wavelet features, surpassing the effectiveness of DVHs.

6.
J Affect Disord ; 363: 282-291, 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.

7.
Neuropsychologia ; 202: 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.

8.
BMC Plant Biol ; 24(1): 727, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080528

RESUMO

BACKGROUND: Fusarium circinatum is the causal agent of pine pitch canker disease, which affects Pinus species worldwide, causing significant economic and ecological losses. In Spain, two Pinus species are most affected by the pathogen; Pinus radiata is highly susceptible, while Pinus pinaster has shown moderate resistance. In F. circinatum-Pinus interactions, phytohormones are known to play a crucial role in plant defense. By comparing species with different degrees of susceptibility, we aimed to elucidate the fundamental mechanisms underlying resistance to the pathogen. For this purpose, we used an integrative approach by combining gene expression and metabolomic phytohormone analyses at 5 and 10 days post inoculation. RESULTS: Gene expression and metabolite phytohormone contents suggested that the moderate resistance of P. pinaster to F. circinatum is determined by the induction of phytohormone signaling and hormone rearrangement beginning at 5 dpi, when symptoms are still not visible. Jasmonic acid was the hormone that showed the greatest increase by 5 dpi, together with the active gibberellic acid 4 and the cytokinin dehydrozeatin; there was also an increase in abscisic acid and salicylic acid by 10 dpi. In contrast, P. radiata hormonal changes were delayed until 10 dpi, when symptoms were already visible; however, this increase was not as high as that in P. pinaster. Indeed, in P. radiata, no differences in jasmonic acid or salicylic acid production were found. Gene expression analysis supported the hormonal data, since the activation of genes related to phytohormone synthesis was observed earlier in P. pinaster than in the susceptible P. radiata. CONCLUSIONS: We determine that the moderate resistance of P. pinaster to F. circinatum is in part a result of early and strong activation of plant phytohormone-based defense responses before symptoms become visible. We suggest that jasmonic acid signaling and production are strongly associated with F. circinatum resistance. In contrast, P. radiata susceptibility was attributed to a delayed response to the fungus at the moment when symptoms were visible. Our results contribute to a better understanding of the phytohormone-based defense mechanism involved in the Pinus-F. circinatum interactions and provide insight into the development of new strategies for disease mitigation.


Assuntos
Fusarium , Pinus , Doenças das Plantas , Reguladores de Crescimento de Plantas , Transdução de Sinais , Fusarium/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Pinus/microbiologia , Pinus/metabolismo , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Resistência à Doença , Ácido Salicílico/metabolismo , Ácido Abscísico/metabolismo
9.
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.

10.
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.

11.
Membranes (Basel) ; 14(7)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-39057655

RESUMO

The CO2 absorption flux while using monoethanolamide (MEA) solution in a spiral-wired channel was significantly enhanced by optimizing both the descending and ascending spiral ring pitch configurations within the filled channel. In this study, two distinct spiral ring pitch configurations were integrated into concentric circular membrane contactors to augment CO2 absorption flux. Spiral rods were strategically inserted to mitigate concentration polarization effects, thereby reducing mass transfer boundary layers and increasing turbulence intensity. A theoretical one-dimensional model was developed to predict absorption flux and concentration distributions across varying MEA absorbent flow rates, CO2 feed flow rates, and inlet CO2 concentrations in the gas feed. Theoretical predictions of absorption flux improvement were validated against experimental results, demonstrating favorable agreement for both ascending and descending spiral ring pitch operations. Interestingly, the results indicated that descending spiral ring pitch operations achieved higher turbulent intensity compared to ascending configurations, thereby alleviating concentration polarization resistance and enhancing CO2 absorption flux with reduced polarization effects. Specifically, under conditions of a 40% inlet CO2 concentration and 5 cm3/s MEA feed flow rate, a notable 83.69% enhancement in absorption flux was achieved compared to using an empty channel configuration. Moreover, a generalized expression for the Sherwood number was derived to predict the mass transfer coefficient for CO2 absorption in concentric circular membrane contactors, providing a practical tool for performance estimation. The economic feasibility of the spiral-wired module was also assessed by evaluating both absorption flux improvement and incremental power consumption. Overall, these findings underscore the effectiveness of optimizing spiral ring pitch configurations in enhancing CO2 absorption flux, offering insights into improving the efficiency and economic viability of CO2 capture technologies.

12.
Sensors (Basel) ; 24(14)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39065903

RESUMO

This study aimed to quantify the influence of the playing surface on workload-related variables (i.e., external load, Rate of perceived exertion (RPE), and mental load) in training sessions with a Spanish professional soccer team. Twenty professional male players from the same soccer team were involved. A total of thirty training sessions related to the preseason period were included. All the players completed training sessions on three playing surfaces: natural turf of poor quality, natural turf of high quality, and third-generation artificial turf. Monitoring during sessions involved assessing internal load (i.e., RPE and mental load) via self-reported questionnaires, and external load using Global Positioning System devices. Linear mixed models showed that RPE was significantly higher on natural turf of high quality than on natural turf of poor quality (p < 0.001). Total distance, relative total distance, the number of accelerations, decelerations, and high metabolic load distance were significantly lower on third-generation artificial turf compared to natural turf of poor quality (p < 0.001) and high quality (p < 0.001). In addition, high-speed running, sprint running distances, and the number of sprints reached higher values on third-generation artificial turf compared to the other two playing surfaces. These findings highlight the need for coaches to consider the type of training surface in soccer to optimize training load planning and prevent injuries.


Assuntos
Esforço Físico , Futebol , Futebol/fisiologia , Humanos , Masculino , Esforço Físico/fisiologia , Adulto , Carga de Trabalho , Desempenho Atlético/fisiologia , Adulto Jovem , Espanha , Corrida/fisiologia , Atletas , Inquéritos e Questionários , Sistemas de Informação Geográfica
13.
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.

14.
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.

15.
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.

16.
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
17.
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.

18.
Eur J Radiol ; 178: 111604, 2024 Sep.
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.


Assuntos
Valva Aórtica , Técnicas de Imagem de Sincronização Cardíaca , Angiografia por Tomografia Computadorizada , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Masculino , Feminino , Angiografia por Tomografia Computadorizada/métodos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Idoso de 80 Anos ou mais , Idoso , Reprodutibilidade dos Testes , Estudos Prospectivos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Eletrocardiografia , Fótons
19.
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.

20.
Auris Nasus Larynx ; 51(4): 738-746, 2024 Aug.
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.


Assuntos
Movimentos Oculares , Humanos , Masculino , Adulto , Feminino , Movimentos Oculares/fisiologia , Adulto Jovem , Força Coriolis , Rotação , Voluntários Saudáveis , Movimentos da Cabeça/fisiologia
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