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1.
Nanomicro Lett ; 16(1): 219, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884690

RESUMO

Doped two-dimensional (2D) materials hold significant promise for advancing many technologies, such as microelectronics, optoelectronics, and energy storage. Herein, n-type 2D oxidized Si nanosheets, namely n-type siloxene (n-SX), are employed as Li-ion battery anodes. Via thermal evaporation of sodium hypophosphite at 275 °C, P atoms are effectively incorporated into siloxene (SX) without compromising its 2D layered morphology and unique Kautsky-type crystal structure. Further, selective nucleophilic substitution occurs, with only Si atoms being replaced by P atoms in the O3≡Si-H tetrahedra. The resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types: (i) P atoms residing in Si sites and (ii) H vacancies. The doping concentrations are varied by controlling the amount of precursors or their mean free paths. Even at 2000 mA g-1, the n-SX electrode with the optimized doping concentration (6.7 × 1019 atoms cm-3) delivers a capacity of 594 mAh g-1 with a 73% capacity retention after 500 cycles. These improvements originate from the enhanced kinetics of charge transport processes, including electronic conduction, charge transfer, and solid-state diffusion. The approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage.

2.
Laryngoscope ; 130(4): E183-E189, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31237699

RESUMO

OBJECTIVES/HYPOTHESIS: Odynophonia is generally regarded as a symptom of a voice disorder. However, a subset of patients with odynophonia have debilitating pain out of proportion to the relatively mild degree of dysphonia and are not responsive to voice therapy. The goals of this study were to 1) describe the symptomatology of this subset of patients and differentiate it from typical odynophonia, 2) propose alternate models to explain this phenomenon of primary odynophonia, and 3) present a new treatment paradigm based on the proposed models. STUDY DESIGN: Case series. METHODS: Inclusion criteria were complaint of persistent pain associated with voicing, normal vocal fold mobility, complete glottic closure, and limited or lack of response of pain to voice therapy. Presenting symptoms, voice evaluation, and treatment outcomes were reviewed. RESULTS: Eleven patients fit the inclusion criteria. The degree of pain did not follow the trajectory of vocal improvement with therapy. The pain was stagnant or worsened with voice exercises. The most dramatic improvement came about in one patient who received false vocal fold Botox injections, and another who received thyrohyoid lidocaine/triamcinolone injection. We propose that these patients had developed primary odynophonia, in which the pain had become self-sustaining and no longer responded to correction of hyperfunctional vocal behavior. The mechanism of pain persistence may involve superior laryngeal neuralgia, cartilaginous or ligamentous inflammation, and/or central sensitization. CONCLUSIONS: A minority of patients have primary odynophonia distinct from typical odynophonia. Direct treatment of pain may be advisable prior to or in conjunction with voice therapy. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E183-E189, 2020.


Assuntos
Manejo da Dor/métodos , Dor/fisiopatologia , Distúrbios da Voz/fisiopatologia , Distúrbios da Voz/terapia , Adolescente , Adulto , Idoso , Disfonia/fisiopatologia , Disfonia/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Retrospectivos , Índice de Gravidade de Doença , Qualidade da Voz , Treinamento da Voz
3.
Adv Sci (Weinh) ; 7(20): 2001738, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33101871

RESUMO

New organic THz generators are designed herein by molecular engineering of the refractive index, phonon mode, and spatial asymmetry. These benzothiazolium crystals simultaneously satisfy the crucial requirements for efficient THz wave generation, including having nonlinear optical chromophores with parallel alignment that provide large optical nonlinearity; good phase matching for enhancing the THz generation efficiency in the near-infrared region; strong intermolecular interactions that provide restraining THz self-absorption; high solubility that promotes good crystal growth ability; and a plate-like crystal morphology with excellent optical quality. Consequently, the as-grown benzothiazolium crystals exhibit excellent characteristics for THz wave generation, particularly at near-infrared pump wavelengths around 1100 nm, which is very promising given the availability of femtosecond laser sources at this wavelength, where current conventional THz generators deliver relatively low optical-to-THz conversion efficiencies. Compared to a 1.0-mm-thick ZnTe crystal as an inorganic benchmark, the 0.28-mm-thick benzothiazolium crystal yields a 19 times higher peak-to-peak THz electric field with a broader spectral bandwidth (>6.5 THz) when pumped at 1140 nm. The present work provides a valuable approach toward realizing organic crystals that can be pumped by near-infrared sources for efficient THz wave generation.

4.
Korean J Gastroenterol ; 47(3): 233-7, 2006 Mar.
Artigo em Coreano | MEDLINE | ID: mdl-16554679

RESUMO

Although adenocarcinoma is a well known complication of chronic inflammatory bowel disease, primary gastrointestinal lymphoma occurring in Crohn's disease is rare. A 40-year-old man with 10 year-history of Crohn's disease had multiple longitudinal ulcerative lesions on descending colon in follow-up colonoscopic examination. Microscopic examination of proximal descending colon revealed peripheral T cell lymphoma and other site of the descending colon was consistent with Crohn's disease. The patient reached complete remission of malignant lymphoma after three cycles of combined chemotherapy. He has been well for 10 months with sulfasalazine maintenance therapy but was admitted to the hospital due to spontaneous bowel perforation of ascending colon. Right hemicolectomy was done, but the patient died of post-surgical recurrent mesenteric abscess and sepsis. To the best of our knowledge, this is the first case of Non-Hodgkin's lymphoma complicating Crohn's disease in Korea which was confirmed by immunohistochemical studies.


Assuntos
Neoplasias do Colo/complicações , Doença de Crohn/complicações , Linfoma de Células T/complicações , Adulto , Neoplasias do Colo/patologia , Humanos , Linfoma de Células T/patologia , Masculino
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