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1.
Small ; 18(21): e2200326, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35285157

RESUMEN

The widespread adoption of Li-ion batteries is currently limited by their unstable electrochemical performance and high flammability under mechanical deformation conditions and a relatively low energy density. Herein, high-energy-density lithium-sulfur (Li-S) batteries are developed for applications in next-generation flexible electronics and electric vehicles with long cruising distances. Freestanding high-S-loading carbon nanotubes cathodes are assembled with a phosphorus (P)-doped carbon interlayer coated on commercial separators. Strategies for the active materials and structural design of both the electrodes and separators are highly efficient for immobilizing the lithium polysulfides via multimodal capturing effects; they significantly improve the electrochemical performance in terms of the redox kinetics and cycling stability. The foldable Li-S cells show stable specific capacities of 850 mAh g-1 over 100 cycles, achieving high gravimetric and volumetric energy densities of 387 Wh kgcell -1 and 395 Wh Lcell -1 , respectively. The Li-S cells show highly durable mechanical flexibilities under severe deformation conditions without short circuit or failure. Finally, the Li-S battery is explored as a light-weight and flexible energy storage device aboard airplane drones to ensure at least fivefold longer flight times than traditional Li-ion batteries. Nanocarbon-based S cathodes and P-doped carbon interlayers offer a promising solution for commercializing rechargeable Li-S batteries.

2.
Hum Brain Mapp ; 42(1): 233-244, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33022826

RESUMEN

Long-term hearing loss in postlingually deaf (PD) adults may lead to brain structural changes that affect the outcomes of cochlear implantation. We studied 94 PD patients who underwent cochlear implantation and 37 patients who were MRI-scanned within 2 weeks after the onset of sudden hearing loss and expected with minimal brain structural changes in relation to deafness. Compared with those with sudden hearing loss, we found lower gray matter (GM) probabilities in bilateral thalami, superior, middle, inferior temporal cortices as well as the central cortical regions corresponding to the movement and sensation of the lips, tongue, and larynx in the PD group. Among these brain areas, the GM in the middle temporal cortex showed negative correlation with disease duration, whereas the other areas displayed positive correlations. Left superior, middle temporal cortical, and bilateral thalamic GMs were the most accurate predictors of post-cochlear implantation word recognition scores (mean absolute error [MAE] = 10.1, r = .82), which was superior to clinical variables used (MAE: 12.1, p < .05). Using the combined brain morphological and clinical features, we achieved the best prediction of the outcome (MAE: 8.51, r = .90). Our findings suggest that the cross-modal plasticity allowing the superior temporal cortex and thalamus to process other modal sensory inputs reverses the initially lower volume when deafness becomes persistent. The middle temporal cortex processing higher-level language comprehension shows persistent negative correlations with disease duration, suggesting this area's association with degraded speech comprehensions due to long-term deafness. Morphological features combined with clinical variables might play a key role in predicting outcomes of cochlear implantation.


Asunto(s)
Implantes Cocleares , Sordera/fisiopatología , Sordera/rehabilitación , Sustancia Gris/anatomía & histología , Corteza Motora/anatomía & histología , Plasticidad Neuronal/fisiología , Evaluación de Resultado en la Atención de Salud , Corteza Somatosensorial/anatomía & histología , Percepción del Habla/fisiología , Lóbulo Temporal/anatomía & histología , Tálamo/anatomía & histología , Adulto , Anciano , Estudios Transversales , Sordera/diagnóstico por imagen , Femenino , Sustancia Gris/diagnóstico por imagen , Pérdida Auditiva Sensorineural/diagnóstico por imagen , Pérdida Auditiva Sensorineural/fisiopatología , Pérdida Auditiva Súbita/diagnóstico por imagen , Pérdida Auditiva Súbita/fisiopatología , Pruebas Auditivas , Humanos , Laringe/fisiología , Labio/fisiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Corteza Motora/diagnóstico por imagen , Corteza Somatosensorial/diagnóstico por imagen , Lóbulo Temporal/diagnóstico por imagen , Tálamo/diagnóstico por imagen , Factores de Tiempo , Lengua/fisiología
3.
Int J Mol Sci ; 22(11)2021 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-34072552

RESUMEN

Indirect evidence has determined the possibility that microplastics (MP) induce constipation, although direct scientific proof for constipation induction in animals remains unclear. To investigate whether oral administration of polystyrene (PS)-MP causes constipation, an alteration in the constipation parameters and mechanisms was analyzed in ICR mice, treated with 0.5 µm PS-MP for 2 weeks. Significant alterations in water consumption, stool weight, stool water contents, and stool morphology were detected in MP treated ICR mice, as compared to Vehicle treated group. Also, the gastrointestinal (GI) motility and intestinal length were decreased, while the histopathological structure and cytological structure of the mid colon were remarkably altered in treated mice. Mice exposed to MP also showed a significant decrease in the GI hormone concentration, muscarinic acetylcholine receptors (mAChRs) expression, and their downstream signaling pathway. Subsequent to MP treatment, concentrations of chloride ion and expressions of its channel (CFTR and CIC-2) were decreased, whereas expressions of aquaporin (AQP)3 and 8 for water transportation were downregulated by activation of the mitogen-activated protein kinase (MAPK)/nuclear factor (NF)-κB signaling pathway. These results are the first to suggest that oral administration of PS-MP induces chronic constipation through the dysregulation of GI motility, mucin secretion, and chloride ion and water transportation in the mid colon.


Asunto(s)
Estreñimiento/diagnóstico , Estreñimiento/etiología , Microplásticos/efectos adversos , Fenotipo , Poliestirenos/efectos adversos , Animales , Conducta Animal , Biomarcadores , Fenómenos Químicos , Cloruros/metabolismo , Colon/patología , Colon/ultraestructura , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Hormonas Gastrointestinales/metabolismo , Motilidad Gastrointestinal , Bombas Iónicas/metabolismo , Ratones , Ratones Endogámicos ICR , Microplásticos/química , Mucinas/metabolismo , Poliestirenos/química , Transducción de Señal , Agua/metabolismo
4.
J Am Chem Soc ; 142(2): 801-814, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31840519

RESUMEN

The electrical relaxation and polarization phenomena of electrospun PVDF (P)/Nafion (N) blended fiber mats ([P/N0.9]M and ß-[P]M) and membranes ([P/N0.9]MM) are compared with those of the solvent-cast membrane of identical composition ([N]C and [P/N0.9]C). The nature of the interactions between the two blended polymer components, that plays a pivotal role in the electrical nature of the resulting materials, is found to be governed by the fabrication method, with those materials obtained via electrospinning undergoing a "reciprocal templating" phenomenon that renders their electrical behavior (especially when in the dry state) significantly different from that of the blended membrane obtained via solvent casting. Broadband Electrical Spectroscopy (BES) demonstrates that the electric response of the blended materials is modulated by polarization phenomena and by α, ß, and γ dielectric relaxation events of Nafion domains supported on ß-PVDF. The coupling between the relaxations of ß-PVDF with those of Nafion matrix is directly correlated to the "reciprocal templating" effect, which modulates the interactions between Nafion and PVDF in electrospun membranes. Two types of conductivity mechanisms characterize the H+ migration within the polymer blends: (1) interdomain H+ migration events by "charge-exchange" phenomena along percolation pathways and (2) H+ exchange between delocalization bodies (DBs) at binding sites at the interface between domains with different ε, size, and morphology. The electrical response of the electrospun membranes also suggests that they do not comprise water clusters with a large size such as those typically observed in pristine Nafion. Rather, the adsorbed H2O molecules, under wet conditions, form thin solvation shells wrapping the polar side chains of the Nafion component. At T = 80 °C, the conductivity of the studied materials decreases in the order [N]C (0.043 S·cm-1) ≈ [P/N0.9]C (0.042 S·cm-1) > [P/N0.9]M (0.031 S·cm-1) > [P/N0.9]MM (0.011 S·cm-1).

5.
Nanotechnology ; 31(47): 475203, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32914759

RESUMEN

The exact direction of the surface energy characterized functional groups of self-assembled monolayers (SAMs) is proposed for achieving enhanced electrical stability of indium gallium zinc oxide (IGZO) semiconductor thin film transistors (TFTs). The SAM treatment, particularly with the SAM functional group having lower surface energy, makes it difficult to adsorb oxygen molecules difficult onto IGZO. Such an effect greatly improves the positive bias stability (PBS) and clockwise hysteresis stability. For NH2 and CF3 functional groups, SAMs with surface energies of 49.4 mJ m-2 and 23.5 mJ m-2, respectively, improved the IGZO TFT PBS from 2.47 V to 0.32 V after the SAM treatment and the IGZO TFT clockwise hysteresis was also enhanced from 0.23 V to 0.11 V without any deterioration of TFT characteristics. Employing lower surface energy functional groups to the SAM, of the same head and body groups, passivates and protects the IGZO backchannel region from oxygen molecules in the atmosphere. Consequently, the enhanced electrical stability of IGZO TFTs can be achieved by the simple and economic SAM treatment.

6.
Nanotechnology ; 2020 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-32764196

RESUMEN

The exact direction, of the surface energy characterized functional group of self-assembled monolayer (SAM), is proposed for achieving the enhanced electrical stability of indium gallium zinc oxide (IGZO) semiconductor thin film transistor (TFT). The SAM treatment, particularly at the SAM functional group having lower surface energy, makes oxygen molecules difficult to be adsorbed onto IGZO. And such an effect much improves positive bias stability (PBS) and clockwise hysteresis stability to the same tendency. For NH2 and CF3 functional group SAMs with surface energies of 49.4 mJ/m2 and 23.5 mJ/m2, respectively, the IGZO TFT PBS was improved from 2.47 V to 0.32 V after the SAM treatment and the IGZO TFT clockwise hysteresis was also enhanced from 0.23 V to 0.11 V without any deterioration of TFT characteristics. Employing lower surface energy functional group to the SAM, of same head group and body group, does passivate and protect the IGZO backchannel region from oxygen molecules in the atmosphere. Consequently, the enhanced electrical stability of IGZO TFT can be achieved by the simple and economic SAM treatment.

7.
Small ; 15(18): e1900235, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30963717

RESUMEN

All-solid-state batteries (ASSBs) have lately received enormous attention for electric vehicle applications because of their exceptional stability by engaging all-solidified cell components. However, there are many formidable hurdles such as low ionic conductivity, interface instability, and difficulty in the manufacturing process, for its practical use. Recently, carbon, one of the representative conducting agents, turns out to largely participate in side reactions with the solid electrolyte, which finally leads to the formation of insulating side products at the interface. Although the battery community mentioned that parasitic reactions are presumably attributed to carbon itself or the generation of electronic conducting paths lowering the kinetic barrier for reactions, the underlying origin for such reactions as well as appropriate solutions have not been provided yet. In this study, for the first time, it is verified that the functional group on carbon is an origin for causing negative effects on interfacial stability and a graphitized hollow nanocarbon as a promising solution for improving-electrochemical performance is introduced. This work offers an invaluable lesson that a relatively minor part, such as a conducting agent, in ASSBs sometimes gives more positive impact on improving electrochemical performance than huge efforts for resolving other parts.

8.
Arch Virol ; 164(1): 213-224, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30317394

RESUMEN

Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important pathogen that affects the global swine industry. The continuous evolution of this virus has made control and prevention difficult, which emphasizes the importance of monitoring currently circulating PRRSV strains. In this study, we investigated the genetic characteristics of whole structural genes of 35 PRRSV-2 isolates that circulated between 2012 and 2017 in Korea. Genetic and phylogenetic analysis demonstrated that a recently identified PRRSV-2 shared a relatively low level of nucleotide sequence identity that ranged from 86.2% to 92.8%; however, they were clustered into four distinct Korean field clades, except KU-N1702, in ORF2-7-based phylogeny. KU-N1702 was closely related to the NADC30-like strains that were identified in the USA and China. Amino acid sequence analysis showed that the GP5 neutralizing epitope was conserved among the KU viruses. In contrast, the viruses had genetic mutations in key residues for viral neutralization within GP5 and M. For minor structural proteins, neutralizing epitopes, aa 41-55 of GP2, 61-75 of GP3, and 51-65 of GP4, were variable among the KU viruses. Bioinformatics demonstrated diversifying evolution within the GP2 and GP4 neutralizing epitopes and the emergence of a novel glycosylation site within the GP3 and GP4 neutralizing epitopes. Taken together, these data provide evidence that Korean PRRSV-2 evolved independently in Korea, with genetic heterogeneity in antigenic regions of structural proteins.


Asunto(s)
Antígenos Virales/genética , Variación Genética , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Proteínas Estructurales Virales/genética , Animales , Filogenia , Síndrome Respiratorio y de la Reproducción Porcina/epidemiología , República de Corea/epidemiología , Porcinos
9.
Clin Otolaryngol ; 44(4): 588-593, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31004465

RESUMEN

OBJECTIVES: Patulous eustachian tube (ET) has been characterised by the visualisation of full-length ET on computed tomography (CT) results. We wanted to investigate the changes of visualised ET lengths by age in supine and sitting positions. DESIGN: Retrospective study. SETTING: Tertiary care academic referral centre. PARTICIPANTS: One hundred subjects who underwent cone beam CT (CBCT) in a sitting position and conventional CT in a supine position for non-otitis-related or dental complaints. MAIN OUTCOME MEASURES: Visualised ET lengths from the nasopharyngeal orifice measured by different positions and ages. RESULTS: Subjects did not show visualisation of full-length ET throughout the study. The visualised ET lengths (9.0 ± 2.5 mm) of the CBCT group were significantly larger than those (6.8 ± 2.3 mm) of the conventional CT group (P < 0.0001).Women showed longer visualised ET lengths than men in CBCT group (P < 0.001). The visualised ET lengths of the CBCT group were consistent or slightly increasing as a function of age (P = 0.06); however, the visualised ET lengths of the conventional CT group decreased as a function of age (P = 0.001). The slopes of regression lines of the two groups were significantly different. CONCLUSIONS: When in the supine position, the ET lengths gradually shortened as the subjects got older, most likely due to venous engorgement and the collapse of surrounding tissues; this finding thus suggests that CT in a supine position is an inappropriate method to diagnose patulous ET. The visualised ET lengths by CBCT in a sitting position were consistent throughout the different ages of the subjects and may be used as a diagnostic test for patulous ET.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Trompa Auditiva/anatomía & histología , Trompa Auditiva/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sedestación , Posición Supina
10.
Eur Radiol ; 28(9): 3685-3691, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29619519

RESUMEN

OBJECTIVES: To evaluate the technical feasibility of direct Eustachian tube catheterisation and subtraction Eustachian tubography in a cadaver model. METHODS: A total of 12 separate sessions were performed on both sides of the Eustachian tube (ET) in six human cadavers. Cadavers were positioned for the submentovertical view on a fluoroscopy table. Endoscopy-guided ET selection was used in the first three cadavers, whereas fluoroscopy-guided ET selection was used in the remaining three. Eustachian tubography was performed by injecting 2 ml of contrast media through a 5-Fr catheter. We recorded the success of ET selection, number of attempts, procedure time, and tubography quality using native and subtraction images (range, 0-3). RESULTS: Both endoscopy- and fluoroscopy-guided selections were successfully performed in five of six sessions (83.3%). There were no statistically significant differences between the endoscopy- and fluoroscopy-guided procedures in terms of the number of attempts, procedure time, rate of immediate contrast leak to the middle ear cavity, and quality of tubography (p > 0.05). An excellent quality of tubography was obtained in 83.3% (10 of 12 sessions) of subtraction images and in 33.3% (4 of 12 sessions) of native images. The tubography quality score was significantly higher for the subtraction images than for the native images (p = 0.04). CONCLUSION: Subtraction Eustachian tubography using direct catheterisation seems to be technically feasible. The entire ET can be well visualised; thus, this technique can be used as a simple tool for assessment of ET function and anatomy. KEY POINTS: • Direct catheterisation of the Eustachian tube is technically feasible. • The entire Eustachian tube could be well visualised by direct Eustachian tubography. • Subtraction Eustachian tubography images have better image quality than native images. • Subtraction Eustachian tubography can provide objective assessment of ET function and anatomy.


Asunto(s)
Cateterismo/métodos , Endoscopía/métodos , Trompa Auditiva/diagnóstico por imagen , Cadáver , Medios de Contraste , Estudios de Factibilidad , Femenino , Fluoroscopía/métodos , Humanos , Masculino , Intensificación de Imagen Radiográfica
11.
J Vasc Interv Radiol ; 29(8): 1187-1193, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30056936

RESUMEN

PURPOSE: To investigate the technical feasibility of stent placement in the cartilaginous portion of the Eustachian tube (ET). MATERIALS AND METHODS: Twelve ETs of 6 cadavers were used. Two different-sized stents were placed on either the right (2.5 mm in diameter) or left (3.5 mm in diameter) side of the ET. The procedural feasibility was assessed by subtraction Eustachian tubography, computed tomography before and after the procedure, and fluoroscopic and endoscopic images. The stent location, inner luminal diameter of the stented ET, radiation dose, procedural time, and fluoroscopy time were analyzed. RESULTS: Stent placement was successful in 11 of 12 cadaveric specimens without procedure-related complications. In the 1 specimen, the balloon catheter with crimped stent was passed into the bony canal of the ET without any resistance. The distal end of the stent was located in the middle ear cavity. Stents were located within the cartilaginous portion of the ET (n = 1), the proximal tip bridging the nasopharyngeal orifice of the ET (n = 5), or the proximal end of the stent protruded from the tubal orifice (n = 5). The mean luminal diameter in the outer segment was significantly smaller than in the middle (P < .001) and inner (P < .001) segments. The mean procedure time was 128 ± 37 seconds. The mean radiation dose and fluoroscopy time of each cadaver were 3235.4 ± 864.8 cGy/cm2 and 139 ± 49 seconds, respectively. CONCLUSIONS: Stent placement of the ET under endoscopic and fluoroscopic guidance is technically feasible in a human cadaver model.


Asunto(s)
Cateterismo/instrumentación , Aleaciones de Cromo , Dilatación/instrumentación , Endoscopía/métodos , Trompa Auditiva , Radiografía Intervencional/métodos , Stents , Cadáver , Trompa Auditiva/diagnóstico por imagen , Estudios de Factibilidad , Fluoroscopía , Humanos , Diseño de Prótesis , Dosis de Radiación , Tomografía Computarizada por Rayos X
12.
Clin Otolaryngol ; 43(6): 1573-1577, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30160368

RESUMEN

OBJECTIVES: To measure the diameter of inflated balloons at different pressures during Eustachian tube (ET) balloon dilation under fluoroscopic guidance. DESIGN: Prospective cohort study. SETTING: Tertiary academic referral centre. PARTICIPANTS: Eighteen patients who underwent ET balloon dilation with use of a balloon catheter, 20 mm long and 6 mm in diameter, under combined endoscopic and fluoroscopic guidance. MAIN OUTCOME MEASURES: Degrees of inflation at three different portions (proximal, middle and distal) of the balloon at controlled pressures (3, 5, 8 and 10 atmospheres [atm]) and at the maximum pressure manually applied. RESULTS: The mean proximal, middle and distal diameters of the inflated balloons were 5.3 ± 0.4 mm, 5.3 ± 0.4 mm and 4.9 ± 0.5 mm at 10 atm. The distal diameters were significantly smaller than middle and proximal diameters at all the pressures (P < 0.01). When compared to the distal diameter (100%, 4.9 ± 0.5 mm) at 10 atm, the distal diameters were 73% (3.6 ± 0.6 mm) at 3 atm, 88% (4.3 ± 0.5 mm) at 5 atm and 96% (4.7 ± 0.4 mm) at 8 atm. The distal diameter (4.1 ± 0.3 mm) at the maximum pressure manually applied was in between those at 3 and 5 atm. CONCLUSIONS: The distal diameter of the balloon increased significantly as a function of the pressure and most (88%) inflation occurred at a low pressure of 5 atm, which was sufficient to inflate the distal diameter of the balloon more than 3 mm. The manual pressurisation could inflate a balloon by as much as could be expected, at between 3 and 5 atm.


Asunto(s)
Cateterismo/instrumentación , Dilatación/instrumentación , Endoscopía/métodos , Trompa Auditiva/diagnóstico por imagen , Fluoroscopía/métodos , Otitis Media con Derrame/diagnóstico , Adulto , Anciano , Enfermedad Crónica , Diseño de Equipo , Trompa Auditiva/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Otitis Media con Derrame/terapia , Presión , Estudios Prospectivos , Tomografía Computarizada por Rayos X
13.
J Surg Oncol ; 116(4): 450-458, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28608492

RESUMEN

BACKGROUND AND OBJECTIVES: Stratification of extranodal extension (ENE) extent has the potential to improve the accuracy of risk estimations in papillary thyroid carcinoma (PTC). This study examined the prognostic importance of nodal factors, including ENE, in PTC patients. METHODS: This study enrolled 2071 consecutive patients with treatment-naïve PTC who underwent thyroidectomy between 2006 and 2010. Microscopic/macroscopic ENE was determined by pathological and operative findings. Univariate and multivariate analyses were used to identify the relationship of factors with recurrence and survival in all study patients and in the node-positive subset. RESULTS: Of 2071 patients, 975 (47.1%) had positive lymph nodes, and 271 (13.1%) and 70 (3.4%) had microscopic and macroscopic ENE, respectively. During a median follow-up of 96 months, 114 (5.5%) patients had post-treatment recurrence. Multivariate analyses showed that, in all patients, the number of positive nodes, lymph node ratio, ENE status, and ATA risk group were independent variables affecting recurrence (P < 0.05). T4 and macroscopic ENE were independent variables associated with shorter overall survival (P < 0.05). Macroscopic ENE was significantly associated with macroscopic extrathyroidal extension. CONCLUSION: Macroscopic ENE has a significant adverse impact on recurrence and survival after treatment for PTC. ENE is considered a high risk factor for recurrence.


Asunto(s)
Carcinoma/mortalidad , Carcinoma/patología , Metástasis Linfática , Recurrencia Local de Neoplasia/patología , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/cirugía , Carcinoma Papilar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia/mortalidad , Pronóstico , República de Corea/epidemiología , Factores de Riesgo , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Adulto Joven
14.
Nanotechnology ; 27(4): 045705, 2016 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-26655693

RESUMEN

Resonance effects in the thickness-dependent ultrafast carrier and phonon dynamics of topological insulator Bi2Se3 are found irrespective of the kind of substrate by measuring thickness-dependent abrupt changes of pump-probe differential-reflectivity signals (ΔR/R) from Bi2Se3 thin films on four different substrates of poly- and single-crystalline (sc-) ZnO, sc-GaN and SiO2. The absolute peak intensity of the ΔR/R is maximized at ∼t C (6 ∼ 9 quintuple layers), which is not directly related to but is very close to the critical thickness below which the energy gap opens. The intensities of the two phonon modes deduced from the oscillatory behaviors superimposed on the ΔR/R profiles are also peaked at ∼t C for the four kinds of substrates, consistent with the thickness-dependent Raman-scattering behaviors. These resonant effects and others are discussed based on possible physical mechanisms including the effects of three-dimensional carrier depletion and intersurface coupling.

15.
HLA ; 103(1): e15291, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37971080

RESUMEN

HLA-DQA1*01:138 is identical to HLA-DQA1*01:03 except for a single nucleotide substitution in exon 3.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Alelos , Análisis de Secuencia de ADN , Cadenas alfa de HLA-DQ/genética
16.
J Korean Assoc Oral Maxillofac Surg ; 50(2): 110-115, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693134

RESUMEN

A 22-year-old male patient presented to the clinic with severe pain in the preauricular area with an inability to completely occlude the jaw. Facial computed tomography and magnetic resonance imaging revealed a well-defined lesion that was tentatively diagnosed as a benign tumor or cystic mass. Surgical approach of a lesion in the condyle is delicate and problematic as many vulnerable anatomical structures are present. There are several methods for surgery in this area. Typically, an extraoral approach is dangerous because of potential injuries to nerves and arteries. The intraoral approach also presents difficulties due to the lack of visibility and accessibility. On occasion, coronoidectomy may be performed. The goal here was to determine an easier and safer new surgical approach to the condyle. We reached the anterior part of the pterygoid plate in the same method as in Le Fort I surgery. From this point, through the external pterygoid muscle, approaching the anterior aspect of the condyle is relatively easy and safe, with minimal damage to the surrounding tissues. Pus was drained at the site, and the lesion was diagnosed as an abscess. Pain and inability to close the mouth resolved without recurrence.

17.
Gut Liver ; 18(1): 77-84, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38013476

RESUMEN

Background/Aims: : This study aimed to review the indications, methods, cooperation, complications, and outcomes of percutaneous endoscopic gastrostomy (PEG). Methods: : Questionnaires were sent to 200 hospitals, of which 62 returned their questionnaires, with a response rate of approximately 30%. Descriptive statistics were calculated to analyze the responses to the questionnaires. Results: : In 2019, a total of 1,052 PEGs were performed in 1,017 patients at 62 hospitals. The main group who underwent PEG was older adult patients with brain disease, particularly stroke. Nutritional supply was an important purpose of the PEG procedure. "The pull method" was the most commonly used for initial PEG insertion. The complications related to PEG were mostly mild, with leakage being the most common. Patients who underwent PEG procedures were primarily educated regarding the post-procedure management and complications related to PEG. Preoperative meetings were skipped at >50% of the institutions. Regarding the cooperation between the nutrition support team (NST) and the physician performing PEG, few endoscopists answered that they cooperated with NST before and after PEG. Moreover, the rate of NST certification obtained by physicians performing PEG and the frequency of attendance at NST-related conferences were relatively low. Conclusions: : This study shows a similar trend to that found in the previous PEG guidelines. However, it covers new aspects, including team-based work for PEG procedure, nutrition support, and education for patients and guardians. Therefore, each medical institution needs to select an appropriate method considering the medical environment and doctor's abilities.


Asunto(s)
Nutrición Enteral , Gastrostomía , Humanos , Anciano , Nutrición Enteral/métodos , Gastrostomía/métodos , Gastroscopía/métodos , Encuestas y Cuestionarios , República de Corea , Estudios Retrospectivos
18.
J Oral Maxillofac Surg ; 71(3): 597-609, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23083507

RESUMEN

PURPOSE: The aim of the present study was to evaluate the postoperative stability after bilateral sagittal split ramus osteotomy (BSSRO) for the treatment of mandibular prognathism, in addition to a posterior ostectomy of the distal segment and mandibular angle resection. PATIENTS AND METHODS: The present retrospective study included patients with mandibular prognathism who were treated with BSSRO at Kangdong Sacred Heart Hospital from July 2007 to July 2011. We assessed the linear changes in the chin position in 17 patients with BSSRO only (control group), 10 with BSSRO and posterior ostectomy of the distal segment (experimental group 1), and 13 with BSSRO and mandibular angle resection (experimental group 2). A cephalogram was taken 2 weeks before surgery and 1 day and 2 months postoperatively. Differences among the groups were determined using 1-way analysis of variance. RESULTS: The demographic and surgical variables were similar among the groups. With regard to the changes observed 1 day to 2 months postoperatively, no statistically significant differences were found; however, the proportion of patients who had highly significant changes (>4 mm) was different. Point B moved forward and upward more than 4 mm in approximately 18% and 12% of patients, respectively, in the control group. However, such movement was not observed in any patient in the experimental group. CONCLUSIONS: Less postoperative instability was present in the experimental groups than in the control group. This might have resulted from the reduced tension in the pterygomasseteric sling and the minimized interference between the bony segments. Therefore, improved stability can be obtained regardless of the type of additional procedures.


Asunto(s)
Maloclusión de Angle Clase III/cirugía , Mandíbula/cirugía , Osteotomía Sagital de Rama Mandibular/métodos , Cuidados Posoperatorios/métodos , Prognatismo/cirugía , Análisis de Varianza , Cefalometría , Humanos , Técnicas de Fijación de Maxilares , Mandíbula/anomalías , Estudios Retrospectivos , Prevención Secundaria
19.
RSC Adv ; 13(39): 27274-27282, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37705990

RESUMEN

Lithium-sulfur batteries (LSB) are an attractive alternative electrochemical energy storage device compared to conventional lithium-ion batteries due to their higher theoretical capacity and energy density. Despite these advantages, it is still difficult to commercialize LSB because of poor electrochemical performance caused by the dissolution of soluble lithium polysulfides (LiPS). To solve these critical issues, a multi-functional separator was prepared using biomass-derived activated carbon (BAC) and a ceramic layer on the polyethylene (PE) separator. For this purpose, BAC was synthesized by a facile one-pot synthesis method by a specifically designed furnace using various forms of milk waste. The multi-functional separator suppresses the effect of LiPS dissolution and increases the Li+ diffusion kinetics. BAC was able to absorb the LiPS shuttle, as confirmed by UV-vis measurements and X-ray photoelectron spectroscopy (XPS). LSB cells assembled using this multi-functional separator show a higher discharge capacity of 1092.5 mA h g-1 at 0.1 C-rate, while commercial PE separators deliver a specific capacity of 811.8 mA h g-1. These novel separators were also able to suppress lithium dendrites during cycling. This work offers a novel and simple approach for streamlining the synthesis process of BAC and applying it to LSB, aiding in the development of sustainable energy sources.

20.
Nat Commun ; 14(1): 1111, 2023 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-36849521

RESUMEN

Transcription factors (TFs) are transported from the cytoplasm to the nucleus and disappear from the nucleus after they regulate gene expression. Here, we discover an unconventional nuclear export of the TF, orthodenticle homeobox 2 (OTX2), in nuclear budding vesicles, which transport OTX2 to the lysosome. We further find that torsin1a (Tor1a) is responsible for scission of the inner nuclear vesicle, which captures OTX2 using the LINC complex. Consistent with this, in cells expressing an ATPase-inactive Tor1aΔE mutant and the LINC (linker of nucleoskeleton and cytoskeleton) breaker KASH2, OTX2 accumulated and formed aggregates in the nucleus. Consequently, in the mice expressing Tor1aΔE and KASH2, OTX2 could not be secreted from the choroid plexus for transfer to the visual cortex, leading to failed development of parvalbumin neurons and reduced visual acuity. Together, our results suggest that unconventional nuclear egress and secretion of OTX2 are necessary not only to induce functional changes in recipient cells but also to prevent aggregation in donor cells.


Asunto(s)
Núcleo Celular , Genes Homeobox , Animales , Ratones , Lisosomas , División Celular , Matriz Nuclear , Vesícula
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