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1.
ACS Omega ; 9(23): 25054-25062, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38882175

RESUMEN

Odor is analyzed on the human olfactometry systems in various steps. The mapping from chemical structures to olfactory perceptions of smell is an extremely challenging task. Scientists have been unable to find a measure to distinguish the perceptual similarity between odorants. In this study, we report regression analysis and visualization based on the odorant chemical space. We discuss the relation between the odor descriptors and their structural diversity for odorants groups associated with each odor descriptor. We studied the influence of structural diversity on the odor descriptor predictability. The results suggest that the diversity of molecular structures, which is associated with the same odor descriptor, is related to the resolutional confusion with the odor descriptor.

2.
Iperception ; 15(3): 20416695241254959, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38765198

RESUMEN

Visual information can be used to plan, start, and coordinate manual movements in obstacle avoidance. An intriguing example of visuomotor coordination is the effect of wing-shaped walls, in which walls are oriented away from or toward a moving agent. A historical story from medieval Japan recounts that wing-shaped walls disrupted the agent's movement more when oriented toward the agent than when oriented away from the agent. This study aimed at examining whether the disruptive effect of wing-shaped walls occurs in a schematic situation represented on a 2D plane. In this study, we conducted psychophysical experiments in which participants were asked to move a stylus from a start point to a goal while avoiding multiple line obstacles that were arranged alternately at a course. In the two experiments, we manipulated the orientation and the size of the visible parts of the obstacles systematically. We found that the obstacles oriented toward the agent produced frequent contacts with the agent and attracted manual movements to the endpoints of obstacles. We discussed possible interpretations of the results in the context of attentional guidance.

3.
Appl Opt ; 63(9): 2256-2262, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38568580

RESUMEN

Compound lens systems with mechanical actuators are used to focus objects at near to far distances. The focal length of ultrasound varifocal liquid crystal (LC) lenses can be controlled by modulating the refractive index spatial distribution of the medium through the acoustic radiation force, resulting in thin and fast-response varifocal lenses. The frequency characteristics of such a lens are evaluated in this paper, and several axisymmetric resonant vibration modes over 20 kHz are observed. The effective lens aperture decreased with the wavelength of the resonant flexural vibration generated on the lens, meaning that this parameter can be controlled with the driving frequency.

4.
Front Psychiatry ; 15: 1328708, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38439795

RESUMEN

Introduction: Individuals with Autism Spectrum Disorder (ASD) show atypical recognition of facial emotions, which has been suggested to stem from arousal and attention allocation. Recent studies have focused on the ability to perceive an average expression from multiple spatially different expressions. This study investigated the effect of autistic traits on temporal ensemble, that is, the perception of the average expression from multiple changing expressions. Methods: We conducted a simplified temporal-ensemble task and analyzed behavioral responses, pupil size, and viewing times for eyes of a face. Participants with and without diagnosis of ASD viewed serial presentations of facial expressions that randomly switched between emotional and neutral. The temporal ratio of the emotional expressions was manipulated. The participants estimated the intensity of the facial emotions for the overall presentation. Results: We obtained three major results: (a) many participants with ASD were less susceptible to the ratio of anger expression for temporal ensembles, (b) they produced significantly greater pupil size for angry expressions (within-participants comparison) and smaller pupil size for sad expressions (between-groups comparison), and (c) pupil size and viewing time to eyes were not correlated with the temporal ensemble. Discussion: These results suggest atypical temporal integration of anger expression and arousal characteristics in individuals with ASD; however, the atypical integration is not fully explained by arousal or attentional allocation.

5.
Eur Urol Oncol ; 7(2): 258-265, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38065702

RESUMEN

BACKGROUND: Urine cytology, although a useful screening method for urothelial carcinoma, lacks sensitivity. As an emerging technology, artificial intelligence (AI) improved image analysis accuracy significantly. OBJECTIVE: To develop a fully automated AI system to assist pathologists in the histological prediction of high-grade urothelial carcinoma (HGUC) from digitized urine cytology slides. DESIGN, SETTING, AND PARTICIPANTS: We digitized 535 consecutive urine cytology slides for AI use. Among these slides, 181 were used for AI development, 39 were used as AI test data to identify HGUC by cell-level classification, and 315 were used as AI test data for slide-level classification. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Out of the 315 slides, 171 were collected immediately prior to bladder biopsy or transurethral resection of bladder tumor, and then outcomes were compared with the histological presence of HGUC in the surgical specimen. The primary aim was to compare AI prediction of the histological presence of HGUC with the pathologist's histological diagnosis of HGUC. Secondary aims were to compare the time required for AI evaluation and concordance between the AI's classification and pathologist's cytology diagnosis. RESULTS AND LIMITATIONS: The AI capability for predicting the histological presence of HGUC was 0.78 for the area under the curve. Comparing the AI predictive performance with pathologists' diagnosis, the AI sensitivity of 63% for histological HGUC prediction was superior to a pathologists' cytology sensitivity of 46% (p = 0.0037). On the contrary, there was no significant difference between the AI specificity of 83% and pathologists' specificity of 89% (p = 0.13), and AI accuracy of 74% and pathologists' accuracy of 68% (p = 0.08). The time required for AI evaluation was 139 s. With respect to the concordance between the AI prediction and pathologist's cytology diagnosis, the accuracy was 86%. Agreements with positive and negative findings were 92% and 84%, respectively. CONCLUSIONS: We developed a fully automated AI system to assist pathologists' histological diagnosis of HGUC using digitized slides. This AI system showed significantly higher sensitivity than a board-certified cytopathologist and may assist pathologists in making urine cytology diagnoses, reducing their workload. PATIENT SUMMARY: In this study, we present a deep learning-based artificial intelligence (AI) system that classifies urine cytology slides according to the Paris system. An automated AI system was developed and validated with 535 consecutive urine cytology slides. The AI predicted histological high-grade urothelial carcinoma from digitized urine cytology slides with superior sensitivity than pathologists, while maintaining comparable specificity and accuracy.


Asunto(s)
Carcinoma de Células Transicionales , Aprendizaje Profundo , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/patología , Carcinoma de Células Transicionales/diagnóstico , Carcinoma de Células Transicionales/patología , Patólogos , Inteligencia Artificial
6.
Nat Commun ; 14(1): 6866, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891189

RESUMEN

Mars lacks a global magnetic field, and instead possesses small-scale crustal magnetic fields, making its magnetic environment fundamentally different from intrinsic magnetospheres like those of Earth or Saturn. Here we report the discovery of magnetospheric ion drift patterns, typical of intrinsic magnetospheres, at Mars using measurements from Mars Atmosphere and Volatile EvolutioN mission. Specifically, we observe wedge-like dispersion structures of hydrogen ions exhibiting butterfly-shaped distributions (pitch angle peaks at 22.5°-45° and 135°-157.5°) within the Martian crustal fields, a feature previously observed only in planetary-scale intrinsic magnetospheres. These dispersed structures are the results of drift motions that fundamentally resemble those observed in intrinsic magnetospheres. Our findings indicate that the Martian magnetosphere embodies an intermediate case where both the unmagnetized and magnetized ion behaviors could be observed because of the wide range of strengths and spatial scales of the crustal magnetic fields around Mars.

7.
Int J Mol Sci ; 24(16)2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37629020

RESUMEN

Extracellular vesicles (EVs), detectable in all bodily fluids, mediate intercellular communication by transporting molecules between cells. The capacity of EVs to transport molecules between distant organs has drawn interest for clinical applications in diagnostics and therapeutics. Although EVs hold potential for nucleic-acid-based and other molecular therapeutics, the lack of standardized technologies, including isolation, characterization, and storage, leaves many challenges for clinical applications, potentially resulting in misinterpretation of crucial findings. Previously, several groups demonstrated the problems of commonly used storage methods that distort EV integrity. This work aims to evaluate the process to optimize the storage conditions of EVs and then characterize them according to the experimental conditions and the models used previously. Our study reports a highly efficient EV storage condition, focusing on EV capacity to protect their molecular cargo from biological, chemical, and mechanical damage. Compared with commonly used EV storage conditions, our EV storage buffer leads to less size and particle number variation at both 4 °C and -80 °C, enhancing the ability to protect EVs while maintaining targeting functionality.


Asunto(s)
Vesículas Extracelulares , Ácidos Nucleicos , Preservación Biológica , Comunicación Celular , Hojas de la Planta
8.
Nat Commun ; 14(1): 4019, 2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37463887

RESUMEN

Mercury's magnetosphere is known to involve fundamental processes releasing particles and energy like at Earth due to the solar wind interaction. The resulting cycle is however much faster and involves acceleration, transport, loss, and recycling of plasma. Direct experimental evidence for the roles of electrons during this cycle is however missing. Here we show that in-situ plasma observations obtained during BepiColombo's first Mercury flyby reveal a compressed magnetosphere hosts of quasi-periodic fluctuations, including the original observation of dynamic phenomena in the post-midnight, southern magnetosphere. The energy-time dispersed electron enhancements support the occurrence of substorm-related, multiple, impulsive injections of electrons that ultimately precipitate onto its surface and induce X-ray fluorescence. These observations reveal that electron injections and subsequent energy-dependent drift now observed throughout Solar System is a universal mechanism that generates aurorae despite the differences in structure and dynamics of the planetary magnetospheres.

9.
Nat Commun ; 14(1): 3142, 2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280247

RESUMEN

Chorus waves are naturally occurring electromagnetic emissions in space and are known to produce highly energetic electrons in the hazardous radiation belt. The characteristic feature of chorus is its fast frequency chirping, whose mechanism remains a long-standing problem. While many theories agree on its nonlinear nature, they differ on whether or how the background magnetic field inhomogeneity plays a key role. Here, using observations of chorus at Mars and Earth, we report direct evidence showing that the chorus chirping rate is consistently related to the background magnetic field inhomogeneity, despite orders of magnitude difference in a key parameter quantifying the inhomogeneity at the two planets. Our results show an extreme test of a recently proposed chorus generation model and confirm the connection between the chirping rate and magnetic field inhomogeneity, opening the door to controlled plasma wave excitation in the laboratory and space.

10.
J Geophys Res Space Phys ; 128(2): e2022JA030989, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37035842

RESUMEN

The Martian crustal magnetic anomalies present a varied, asymmetric obstacle to the imposing draped interplanetary magnetic field (IMF) and solar wind plasma. Magnetic reconnection, a ubiquitous plasma phenomenon responsible for transferring energy and changing magnetic field topology, has been observed throughout the Martian magnetosphere. More specifically, reconnection can occur as a result of the interaction between crustal fields and the IMF, however, the global implications and changes to the overall magnetospheric structure of Mars have yet to be fully understood. Here, we present an analysis to determine these global implications by investigating external conditions that favor reconnection with the underlying crustal anomalies at Mars. To do so, we plot a map of the crustal anomalies' strength and orientation compiled from magnetic field data collected throughout the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. Then, we create "shear maps" which calculate and plot the angle of shear between the crustal fields and a chosen external field orientation. From there we define a "shear index" to quantify the susceptibility of a region to undergo reconnection based on a given overlaid, external field orientation and the resulting shear map for that region. We demonstrate that the shear analysis technique augments analysis of local reconnection events and suggests southward IMF conditions should favor dayside magnetic reconnection on a more global scale at Mars.

11.
Sensors (Basel) ; 23(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37050574

RESUMEN

The core of a Gigahertz Spin Rotation (GSR) sensor, a compact and highly sensitive magnetic sensor, is composed of Co-Fe-based amorphous magnetic wire with a diameter of 10 µm. Observations of the magnetic domain structure showed that this magnetic wire has unusual magnetic noise characteristics. Bamboo-shaped magnetic domains a few hundred micrometers in width were observed to form inside the wire, and smaller domains a few micrometers across were observed to form inside these larger domains. The magnetic domain pattern changed abruptly when an external magnetic field was applied to the wire. Herein is shown how these changes may be a source of magnetic noise in the wire.

12.
R Soc Open Sci ; 10(1): 220585, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36686551

RESUMEN

A series of multiple facial expressions can be temporally perceived as an averaged facial expression in a process known as ensemble perception. This study examined the effect of temporal parameters on the perceived intensity of facial expression in each emotion, and how the effect varies with autistic traits in typically developing people. In the experiment, we presented facial expressions that switched from emotional to neutral expressions, and vice versa, for 3 s. Participants rated the overall perceived intensity of the facial emotions as a whole rather than rating individual items within the set. For the two tasks, a ratio of duration of emotional faces to duration of neutral faces (emotional ratio) and the timing for transitions were manipulated individually. The results showed that the intensity of facial emotion was perceived more strongly when the presentation ratio increased and when the emotional expression was presented last. The effects were different among the emotions (e.g. relatively weak in the anger expression). Moreover, the perceived intensity of angry expressions decreased with autistic traits. These results suggest that the properties and individual differences in the facial ensemble of each emotion affect emotional perceptions.

14.
Eur Arch Otorhinolaryngol ; 280(1): 419-423, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36001135

RESUMEN

PURPOSE: Due to difficulties in breath holding, patients who undergo total laryngectomy may be prone to the development of chronic constipation. However, few reports have described chronic constipation in laryngectomized patients, and no report has described prevalence in patients who have undergone total pharyngolaryngectomy. METHODS: We conducted a cross-sectional study to investigate the prevalence of chronic constipation after laryngectomy and evaluated the relationship between patient characteristics and chronic constipation. Information on patient characteristics and the details of surgery were obtained from medical records and an original questionnaire survey in 50 patients. RESULTS: The prevalence of chronic constipation after laryngectomy was high, at 36%, with 18 cases. Patients who received total laryngectomy were significantly more likely to have chronic constipation than those who received total pharyngolaryngectomy (47.1% vs 12.5%, P = 0.026), who had a similar prevalence to the general public. Furthermore, the period from surgery to survey was significantly shorter in the constipation group than in the no constipation group (P = 0.043). CONCLUSIONS: The prevalence of chronic constipation in patients who had undergone laryngectomy for head and neck cancer was high, particularly in patients who received total laryngectomy and in those with only a short period since surgery.


Asunto(s)
Neoplasias de Cabeza y Cuello , Laringectomía , Humanos , Laringectomía/efectos adversos , Estudios Transversales
15.
Sci Rep ; 12(1): 17649, 2022 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-36271109

RESUMEN

The zebrafish is widely used as a model in biological studies. In particular, the heart rate and cortisol levels of zebrafish are commonly measured to elucidate the pharmacological effects of chemical substances. Meanwhile, although ventilation is also an important physiological index reflecting emotion-like states, few studies have evaluated the effects of chemicals on ventilation in adult zebrafish. In this study, we assessed whether it is possible to evaluate the pharmacological effects elicited by caffeine in adult zebrafish under free-swimming conditions. We measured the ventilation in adult zebrafish exposed to multiple concentrations of caffeine under restraint and free-swimming conditions and evaluated the pharmacological effects of caffeine using linear mixed model analysis. In addition, results of electrocardiogram analysis and swimming speeds were compared with those in previous reports to ensure that an appropriate dose of caffeine was administered. Under restraint conditions, caffeine significantly decreased heart rate and increased ventilation in a concentration-dependent manner. Under free-swimming conditions, the ventilation rate significantly increased with increasing caffeine concentration. These results indicate that the pharmacological effects elicited by chemicals on ventilation can be evaluated in free-swimming zebrafish.


Asunto(s)
Cafeína , Pez Cebra , Animales , Pez Cebra/fisiología , Cafeína/farmacología , Natación , Hidrocortisona/farmacología , Respiración , Conducta Animal
16.
Geophys Res Lett ; 49(12): e2022GL098007, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35865912

RESUMEN

The Martian magnetotail exhibits a highly twisted configuration, shifting in response to changes in polarity of the interplanetary magnetic field's (IMF) dawn-dusk (B Y) component. Here, we analyze ∼6000 MAVEN orbits to quantify the degree of magnetotail twisting (θ Twist) and assess variations as a function of (a) strong planetary crustal field location, (b) Mars season, and (c) downtail distance. The results demonstrate that θ Twist is larger for a duskward (+B Y) IMF orientation a majority of the time. This preference is likely due to the local orientation of crustal magnetic fields across the surface of Mars, where a +B Y IMF orientation presents ideal conditions for magnetic reconnection to occur. Additionally, we observe an increase in θ Twist with downtail distance, similar to Earth's magnetotail. These findings suggest that coupling between the IMF and moderate-to-weak crustal field regions may play a major role in determining the magnetospheric structure at Mars.

17.
Artículo en Inglés | MEDLINE | ID: mdl-35905066

RESUMEN

A varifocal concave-convex lens using ultrasound and transparent viscoelastic gel is reported. The configuration of the lens is simple and thin, consisting of four pieces of a piezoelectric ultrasound transducer, a glass disk, and a transparent silicone gel film. It uses a combination of the ultrasound resonant flexural standing- and traveling-wave modes excited by in-phase and four-phase drives so that the lens can change its shape to both concave and convex by switching the resonance mode with the same structure. The acoustic radiation force (ARF) originated from the resonant flexural vibration modes changed the surface profile of the gel. Convex and concave deformation were generated at the center of the lens at the resonance frequencies of 38 and 60 kHz, respectively, indicating that a varifocal concave-convex lens could be fabricated by controlling the driving frequency, voltage amplitude, and phase differences among the ultrasound transducers. The deformational displacement on the lens surface and the change in the focal length increased with the input voltage amplitude. The optical microscopic images observed through the lens were enlarged 1.28× (reduced 0.92× ) in the convex (concave) mode with 20 [Formula: see text]. The response time for focusing and the temperature stability under operation were evaluated. By switching the resonance vibration modes of the lens through the input signals to multiple ultrasound transducers, the variable-focus function with both concave and convex lenses was achieved in the same configuration.


Asunto(s)
Lentes , Vibración , Diseño de Equipo , Microscopía , Ultrasonografía
18.
Audiol Neurootol ; 27(5): 418-426, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35512660

RESUMEN

INTRODUCTION: The prognosis of Bell's palsy, idiopathic facial nerve palsy (FNP), is usually predicted by electroneuronography in subacute phase. However, it would be ideal to establish a reliable and objective examination applicable in acute phase to predict the prognosis of FNP. Immune-nutritional status (INS) calculated from peripheral blood examination is recently reported as the prognostic factor in various disease. However, the validity of INS as the prognostic factor in Bell's palsy is not well known. Thus, we conducted a retrospective study to investigate the usefulness of INS as prognostic predictors of Bell's palsy. METHODS: We reviewed the medical records of 79 patients with Bell's palsy and divided into two groups as "complete recovery" and "incomplete recovery" groups. Clinical features such as severity of FNP and INS, including neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), prognostic nutritional index (PNI), and controlling nutrition status (CONUT) score, were assessed. RESULTS: In univariate analysis, statistically significant differences were observed in clinical score of facial movement, NLR, LMR, PNI, and CONUT score at the initial examination between the two groups (p < 0.05). Furthermore, in multivariate analysis, statistically significant differences were also observed in facial movement score and PNI at the initial examination (p < 0.05). CONCLUSION: Immune and nutritional condition play important roles in the pathogenesis of Bell's palsy, suggesting that INS would be one of the useful prognostic factors in Bell's palsy.


Asunto(s)
Parálisis de Bell , Parálisis Facial , Parálisis de Bell/diagnóstico , Parálisis de Bell/etiología , Humanos , Estado Nutricional , Pronóstico , Estudios Retrospectivos
19.
ACS Omega ; 7(10): 8581-8590, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35309498

RESUMEN

A comparative study is presented. The method via chemical variational autoencoder (VAE) and the method via similarity search are compared, focusing on their generation ability for new functional molecular design. Focusing on the natural porphyra-334 as a model molecule, we generated three groups: molecules of mycosporine-like amino acids (MAAs) as seeds (G SEEDS ), molecules generated via chemical VAE (G VAE ) and molecules gathered via similarity search (G SIM ). The number of molecules that satisfy the condition for the light absorption ability of porphyra-334 in G SEEDS , G VAE , and G SIM are 52, 138, and 6, respectively. The method via chemical VAE shows a promising potential for future molecular design. By using quantum chemistry wave function properties for chemical VAE, we find new molecules that are comparable to porphyra-334, including some with unexpected geometries. At the end, we show a group of molecules found with this method.

20.
Anticancer Res ; 42(3): 1607-1613, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35220258

RESUMEN

BACKGROUND/AIM: There are no real-world comparative data of nivolumab doses of 3 mg/kg and 240 mg/body for recurrent/metastatic squamous cell carcinoma of the head and neck (R/M SCCHN). We investigated the efficacy and safety of nivolumab in treating recurrent/metastatic squamous cell carcinoma of the head and neck (R/M SCCHN) at different doses using real-world data. PATIENTS AND METHODS: R/M SCCHN patients who received nivolumab were divided into the 3 mg/kg and 240 mg/body groups and retrospectively examined for efficacy and safety. RESULTS: A total of 199 patients (3 mg/kg and 240 mg/body, 88 and 111 patients, respectively) were included. The 3 mg/kg vs. 240 mg/body groups had similar overall response rates (15% vs. 25, p=0.15), disease control rates (46% vs. 57%, p=0.15), overall survival (9.5 months vs. 10.9 months), and progression-free survival (3.7 months vs. 3.8 months, p=0.95). The incidence of immune-related adverse events was also similar in both groups. CONCLUSION: In R/M SCCHN patients, nivolumab showed similar efficacy and safety at doses of 3 mg/kg and 240 mg/body.


Asunto(s)
Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/administración & dosificación , Recurrencia Local de Neoplasia , Nivolumab/administración & dosificación , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias de Cabeza y Cuello/inmunología , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Humanos , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Masculino , Persona de Mediana Edad , Nivolumab/efectos adversos , Supervivencia sin Progresión , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/inmunología , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/secundario , Factores de Tiempo , Tokio , Adulto Joven
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