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1.
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.

2.
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
3.
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.

4.
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
5.
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.

6.
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
7.
J Am Chem Soc ; 141(39): 15649-15655, 2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31491075

RESUMEN

A layered metal-organic framework (MOF) comprising extra-large nanographene sheets, HBCMOF, was successfully synthesized using a dicarboxylic acid derivative of hexa-peri-hexabenzocoronene (HBCLH2), and its structure was characterized by single-crystal X-ray diffraction analysis. The crystal structure shows that 2D layers composed of a dinuclear Zn2+ complex unit and HBCL are located on top of each other through multiple weak interlayer bonds, affording HBCMOF, having three dimensionally connected nanopores with large nanographene surfaces. The HBC-based nanographene sheets are anchored to the MOF framework via two zinc carboxylate linkages and therefore have an axial rotational freedom. The sorption isotherms of gaseous molecules such as carbon dioxide and hydrocarbons (acetylene, propane, propylene, benzene, and cyclohexane) on HBCMOF all displayed a hysteretic profile with reversible structural changes, as observed by in situ powder X-ray diffraction studies.

8.
Appl Environ Microbiol ; 85(6)2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30610075

RESUMEN

Lactobacillus gasseri LA327, isolated from the large intestine tissue in humans, is a bacteriocinogenic strain with two kinds of class IIb bacteriocin structural genes, i.e., those for gassericin T (GT) and acidocin LF221A (Acd LF221A). In this study, DNA sequencing of the genes for GT and Acd LF221A from L. gasseri LA327 revealed that the amino acid sequences for GT corresponded with those for GT genes, except for GatK (histidine kinase). However, Acd LF221A genes had analogues which differed in at least one amino acid residue, to encode a class IIb bacteriocin designated gassericin S (GS). The LA327 strain retained antimicrobial activity after the deletion of the GT structural genes (gatAX); however, both GS and GT activities were lost by deletion of the putative ABC transporter gene (gatT). This indicates that the LA327 strain produces GS and GT and that GS secretion is performed via GT genes with the inclusion of gatT Homologous expression using deletion mutants of GS and GT, each containing a single peptide, elucidated that GS (GasAX) and GT (GatAX) showed synergistic activity as class IIb bacteriocins and that no synergistic activity was observed between GS and GT peptides. The molecular mass of GS was estimated to be theoretical ca. 5,400 Da by in situ activity assay after SDS-PAGE, clarifying that GS was actually expressed as an active class IIb bacteriocin. Furthermore, the stability of expressed GS to pH, heat, and protease was determined.IMPORTANCE Bacteriocins are regarded as potential alternatives for antibiotics in the absence of highly resistant bacteria. In particular, two-peptide (class IIb) bacteriocins exhibit the maximum activity through the synergy of two components, and their antimicrobial spectra are known to be relatively wide. However, there are few reports of synergistic activity of class IIb bacteriocins determined by isolation and purification of individual peptides. Our results clarified the interaction of each class IIb component peptide for GT and GS via the construction of homologous mutants, which were not dependent on the purification. These data may contribute to understanding the mechanisms of action by which class IIb bacteriocins exhibit wide antibacterial spectra.


Asunto(s)
Bacteriocinas/biosíntesis , Lactobacillus gasseri/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Bacteriocinas/química , Bacteriocinas/genética , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Lactobacillus gasseri/genética , Operón
9.
Mod Rheumatol ; 27(6): 1098-1100, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25867226

RESUMEN

Chronic infantile neurological, cutaneous, and articular (CINCA) syndrome is a systemic autoinflammatory disease caused by increased production of interleukin (IL)-1ß. We present a case of CINCA syndrome followed up to skeletal maturity. Joint contracture and valgus deformity of the knee had developed before diagnosis. Surgical interventions by soft tissue release and hemiepiphysiodesis improved the contracture and the deformity, and IL-1 receptor antagonist dramatically controlled systemic inflammation, and the patient lives without any disabilities.


Asunto(s)
Contractura/diagnóstico , Síndromes Periódicos Asociados a Criopirina/diagnóstico , Antirreumáticos/uso terapéutico , Contractura/tratamiento farmacológico , Contractura/cirugía , Síndromes Periódicos Asociados a Criopirina/tratamiento farmacológico , Síndromes Periódicos Asociados a Criopirina/cirugía , Humanos , Lactante , Proteína Antagonista del Receptor de Interleucina 1/uso terapéutico , Articulación de la Rodilla/patología , Articulación de la Rodilla/cirugía , Masculino
10.
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.

11.
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.

12.
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.

13.
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
14.
Int J Syst Evol Microbiol ; 63(Pt 5): 1690-1695, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22922533

RESUMEN

Gram-negative bacteria of the genus Xenorhabdus exhibit a mutualistic association with steinernematid entomopathogenic nematodes and a pathogenic relationship with insects. Here we describe two isolates of the entomopathogenic nematode Steinernema aciari collected from China and Japan. 16S rRNA gene sequence similarity and phylogenetic analysis indicated that the isolates obtained from S. aciari belonged to the genus Xenorhabdus. Multilocus sequence analysis based on five universal protein-coding gene sequences revealed that the isolates were closely related to Xenorhabdus ehlersii DSM 16337(T) and Xenorhabdus griffiniae ID10(T) but that they exhibited <97 % sequence similarity with these reference strains, which indicated that the isolates were distinct from previously described species. Based on these genetic differences and several differential phenotypic traits, we propose that the isolates represent a novel species of the genus Xenorhabdus, for which we propose the name Xenorhabdus ishibashii sp. nov. The type strain is GDh7(T) ( = DSM 22670(T)  = CGMCC 1.9166(T)).


Asunto(s)
Filogenia , Rabdítidos/microbiología , Xenorhabdus/clasificación , Animales , Técnicas de Tipificación Bacteriana , China , ADN Bacteriano/genética , Genes Bacterianos , Japón , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Xenorhabdus/genética , Xenorhabdus/aislamiento & purificación
15.
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.

16.
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.

17.
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.

19.
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.

20.
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.

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