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2.
Nanotechnology ; 33(37)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35667365

RESUMO

Ta-based high-κdielectrics can be synthesized via the oxidation of TaS2films. In this study, we investigated the wet and dry oxidation of TaS2films via thermal annealing and plasma irradiation, respectively. The specific vibration observed via Raman spectroscopy, the bonding states observed via x-ray photoelectron spectroscopy, and capacitance measurements confirmed the oxidation of TaS2films with a dielectric constant of ∼14.9. Moreover, the electrical transport of the TaS2films along the in-plane direction indicated a change in conductivity before and after the oxidation. The thickness of the oxidized film was estimated. Accordingly, the layer-by-layer oxidation was limited to approximately 50 nm via plasma irradiation, whereas the TaS2films within 150 nm were fully oxidized via thermal annealing in ambient air. Therefore, a Ta-oxide/TaS2structure was fabricated as a stack material of insulator and metal when the thickness of the pristine film was greater than 50 nm. In addition, Ta-oxide films were integrated into bottom-gated two-dimensional (2D) field-effect transistors (FETs) using the dry transfer method. 2D FETs with multilayer MoTe2and MoS2films asp-type andn-type channels, respectively, were successfully fabricated. In particular, the Ta-oxide film synthesized via dry oxidation was used as a gate dielectric, and the device process could be simplified because the Ta-oxide/TaS2heterostructure can function as a stack material for gate insulators and gate electrodes. An anti-ambipolar transistor consisting of an MoTe2/MoS2heterojunction was also fabricated. For the transfer characteristics, a relatively sharp on-state bias range below 10 V and sufficiently high peak-to-valley ratio of 106atVDS = 3 V were obtained using the high-κ gate dielectric of Ta-oxide despite the presence of the multilayer channels (∼20 nm).

4.
J Am Chem Soc ; 143(15): 5698-5708, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33827207

RESUMO

Cu2SnxGe1-xS3 (CTGS) particles were synthesized via a solid-state reaction and assessed, for the first time, as both photocatalysts and photocathode materials for hydrogen evolution from water. Variations in the crystal and electronic structure with the Sn/Ge ratio were examined experimentally and theoretically. The incorporation of Ge was found to negatively shift the conduction band minimum, such that the bandgap energy could be tuned over the range 0.77-1.49 eV, and also increased the driving force for the photoexcited electrons involved in hydrogen evolution. The effects of the Sn/Ge ratio and of Cu deficiency on the photoelectrochemical performance of Cu2SnxGe1-xS3 and CuySn0.38Ge0.62S3 (1.86 < y < 2.1) based photocathodes were evaluated under simulated sunlight. Both variations in the band-edge position and the presence of a secondary impurity phase affected the performance, such that a particulate Cu1.9Sn0.38Ge0.62S3 photocathode was the highest performing specimen. This cathode gave a half-cell solar-to-hydrogen energy conversion efficiency of 0.56% at 0.18 V vs a reversible hydrogen electrode (RHE) and an incident-photon-to-current conversion efficiency of 18% in response to 550 nm monochromatic light at 0 VRHE. More importantly, these CTGS particles also demonstrated significant photocatalytic activity during hydrogen evolution and were responsive to radiation up to 1500 nm, representing infrared light. The chemical stability, lack of toxicity, and high activity during hydrogen evolution of the present CTGS particles suggest that they may be potential alternatives to visible/infrared light responsive Cu-chalcogenide photocatalysts and photocathode materials such as Cu(In,Ga)(S,Se)2 and Cu2ZnSnS4.

5.
J Dermatol ; 48(7): 1094-1097, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33755237

RESUMO

A tick infestation is one of the most common arthropod-related skin diseases in Hokkaido, the northernmost island of Japan. Ticks also act as an infectious disease vector for humans. Tick-borne encephalitis (TBE), a highly mortal central nervous system infection caused by TBE virus (TBEV), has sporadically occurred there recently. However, there have been no epidemiological data on the current surveillance of human tick bites and the prevalence of TBEV in human-feeding ticks. This study was performed to clarify those indeterminate issues. One hundred and fifty-three ixodid ticks feeding on humans were collected from 150 outpatients in Hokkaido during the season of April to August 2018. None of the cases showed any infectious symptoms. These ticks were morphologically identified to species, and a cytopathic assay on baby hamster kidney cells was carried out to detect TBEV from each tick. The tick collection consisted of 108 Ixodes persulcatus (one nymph and 107 adult females), 44 female Ixodes ovatus, and one female Haemaphysalis japonica. No tick extracts showed positive results of the cytopathic assay, suggesting the non-existence of TBEV in the present specimens. However, the survey to detect TBEV from human-feeding ticks is still important to monitor the occurrence of TBE, because human tick bites by I. ovatus, a possible vector of TBEV, are increasing even in the northern and eastern areas of Hokkaido.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Ixodes , Animais , Feminino , Humanos , Japão , Ninfa
6.
Glob Chall ; 3(8): 1800107, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31565389

RESUMO

Graphite whiskers (GWs) are obtained from coffee grounds (CGs) treated at 2500 °C for 1 h in the presence of Ar gas at 1 atm. The majority of the GWs formed inside the CGs shell are rod-like with a conical tip with diameter and length in the range between 1 to 3 µm and 4 to 10 µm, respectively. At first, the carbon layer might be grown in a turbostratic manner, and then progressively graphitized at higher temperature. The strong G' peak intensity might be induced by the disclination of graphitized carbon layers.

7.
Sci Rep ; 9(1): 7871, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133669

RESUMO

Here, we present a facile technique for synthesis of graphene nanosheet (GNS)-grafted double-walled carbon nanotube (DWCNT) hybrid carbon nanostructures (here after referred to as G-DWCNTs) by directly growing GNSs along the sidewalls of DWCNTs using a two-step chemical vapor deposition (CVD). DWCNTs were synthesized by floating catalyst CVD at 1300 °C using ferrocene and thiophene dissolved in ethanol. Then, GNSs were grafted onto the synthesized DWCNT bundles by thermal CVD at 1300 °C using ethanol. The sharp-edged petal-like structure of GNSs were grown along the sidewalls of DWCNT bundles while maintaining the one-dimensional structure of DWCNT. Next, DWCNTs and G-DWCNTs were dispersed in ethanol, then deposited on the paper using vacuum filtration method and used for ethanol detection. G-DWCNTs sensor exhibited a 3-fold improvement in the response to ethanol vapor compared to the DWCNTs sensor. The sensing mechanism of DWCNTs and G-DWCNTs can be described in terms of charge transfer between the gas molecules and sensing material. These results demonstrate that the facile technique by two-step CVD method provides a promising approach for simple and low-cost technique to synthesize the hybrid nanostructure of GNSs and DWCNTs. The new hybrid carbon nanostructures are attractive for gas sensing application.

11.
Sci Rep ; 7: 40259, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-28074847

RESUMO

Nitrogen-doped porous activated carbon monoliths (NDP-ACMs) have long been the most desirable materials for supercapacitors. Unique to the conventional template based Lewis acid/base activation methods, herein, we report on a simple yet practicable novel approach to production of the three-dimensional NDP-ACMs (3D-NDP-ACMs). Polyacrylonitrile (PAN) contained carbon nanotubes (CNTs), being pre-dispersed into a tubular level of dispersions, were used as the starting material and the 3D-NDP-ACMs were obtained via a template-free process. First, a continuous mesoporous PAN/CNT based 3D monolith was established by using a template-free temperature-induced phase separation (TTPS). Second, a nitrogen-doped 3D-ACM with a surface area of 613.8 m2/g and a pore volume 0.366 cm3/g was obtained. A typical supercapacitor with our 3D-NDP-ACMs as the functioning electrodes gave a specific capacitance stabilized at 216 F/g even after 3000 cycles, demonstrating the advantageous performance of the PAN/CNT based 3D-NDP-ACMs.

12.
J Dermatol Case Rep ; 8(1): 16-9, 2014 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-24748906

RESUMO

BACKGROUND: Cutaneous adverse events associated with the use of epidermal growth factor receptor inhibitors, such as cetuximab are relatively common. Although there are reports about possible treatments for acne or acneiform lesions induced by cetuximab, there are only few reports of prospective studies. OBJECTIVE: The aim of the study was to analyze the efficacy of varius treatment modalities and their combinations in patients with acneiform eruptions caused by cetuximab. PATIENTS AND METHODS: We studied 14 patients treated with an epidermal growth factor receptor inhibitors, including 7 patients cetuximab, who developed acneiform eruptions in the course of therapy. All patients were diagnosed as grade II according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.0. A corticosteroid ointment, tacrolimus ointment, and ketoconazole ointment were used in a randomized manner. Oral therapy included administration of antihistaminic drugs, tetracycline, a cyclooxygenase inhibitor, or a macrolide. We measured the numer of days required to achieve improvement from grade II to grade I during cetuximab treatment. RESULTS: Our results showed that tetracycline treatment may shorten the period needed to achieve improvement. Ketoconazole cream and a combination of oral tetracycline and topical ketoconazole also significantly shortened this period. CONCLUSION: The results of our short case study may indicate that a combitation therapy of oral tetracyclin and topical ketokonazole is most effective in the therapy of patients with acneiform eruptions caused by cetuximab.

13.
J Med Case Rep ; 8: 17, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24428950

RESUMO

INTRODUCTION: Myocardial sarcoidosis is known as a significant complication of sarcoidosis, but Holter electrocardiographic monitoring or echocardiograms might not be sensitive enough to detect cardiac involvement. While gallium scintigraphy has been recommended, 18F-fluorodeoxyglucose positron emission tomography-computed tomography might be more sensitive to detect sarcoidosis. CASE PRESENTATIONS: This report comprises the cases of 12 Japanese patients. Two were male, and ten were female. Their age range was between 32 and 93 years. The average age of the patients was 63. We found internal involvement of sarcoidosis in eight (89%) of nine patients by positron emission tomography-computed tomography and in two (67%) of three patients by gallium scintigraphy. Myocardial sarcoidosis was detected in four (33%) of twelve patients, and specifically in three (75%) of four facial multiple plaque type sarcoidosis patients. CONCLUSION: The myocardial lesions detected by positron emission tomography-computed tomography could not be detected with conventional electrocardiogram or echogram. Positron emission tomography-computed tomography can detect sarcoid lesions of the whole body and is useful for the follow up of patients. We recommend positron emission tomography-computed tomography for those patients having cutaneous sarcoidosis, especially facial multiple plaque type sarcoidosis.

14.
J Dermatol ; 40(5): 370-3, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23414205

RESUMO

Personality and emotional factors are supposed to influence the course of skin diseases, such as psoriasis and atopic dermatitis. Few reports exist, however, showing distinct personality traits among patients with psoriasis, atopic dermatitis patients and healthy controls. The aim of the present study was to examine personality differences among psoriasis patients, atopic dermatitis patients and healthy controls in Japan. A total number of 51 psoriasis patients, 97 atopic dermatitis patients and 48 healthy individuals were enrolled in the study. Questionnaires of Yatabe-Guilford Personality Inventory were administered individually. These groups were evaluated by 12 dimensions of temperaments. According to the dimension scores, personality was defined as five groups. Atopic dermatitis patients showed significantly higher scores regarding temperaments of depression, feelings of inferiority, nervousness and lack of objectivity than psoriasis patients. Regarding a temperament of cyclic tendency and lack of cooperativeness, female atopic dermatitis patients showed significantly higher scores than female psoriasis patients. Regarding general activity, female atopic dermatitis patients showed significantly lower scores than those of female psoriasis patients. No significant difference in scores of temperaments of lack of agreeableness, rhathymia, thinking extraversion, ascendance and social extraversion were detected among psoriasis patients, atopic dermatitis patients and healthy controls. The personalities of male psoriasis patients were significantly different from those of atopic dermatitis patients and healthy controls. Female psoriasis patients showed a significantly different personality profile from that of atopic dermatitis patients, but not from healthy controls. Japanese psoriasis and atopic dermatitis patients show distinct personality profiles suggesting that specific a psychosomatic approach may be required during the treatment.


Assuntos
Dermatite Atópica/psicologia , Psoríase/psicologia , Temperamento , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Inventário de Personalidade , Adulto Jovem
18.
J Dermatolog Treat ; 23(2): 112-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21254847

RESUMO

Although ciclosporin is useful for atopic dermatitis (AD), appropriate dosage and therapeutic drug monitoring (TDM) has been performed only by post-prandial ciclosporin administration. We administered ciclosporin pre-prandially to eight severe adult AD patients (four cases of erythrodermic AD, three cases of AD recalcitrant to standard therapy, and one AD case with numerous pruriginous lesions). Blood concentrations of ciclosporin at various dosages were measured and appropriate dosage in terms of therapeutic efficacy was analyzed by using the area under the concentration curve (AUC). AUC was estimated by the C1 (obtained serum concentration of ciclosporin at 1 hour after ciclosporin administration), C2 (concentration of ciclosporin at 2 hours) and C4 (concentration of ciclosporin at 4 hours) concentrations of ciclosporin. The trough levels of ciclosporin with 200 mg/day, 150 mg/day, and 100 mg/day administration were 96.5 ng/ml, 66.4 ng/ml, and 75.3 ng/ml, respectively. The peak serum concentration (C(max)) was obtained at 1 hour (C1) in most cases. The AUC of 0-4 hours (AUC 0-4) were 2099.5 ng · h/ml (200 mg/day), 1782.6 ng · h/ml (150 mg/day) and 1696.2 ng · h/ml (100 mg/day). VAS scores of itching and blood eosinophil counts were decreased significantly by the ciclosporin treatment. Pre-prandial administration of a relatively low dose of ciclosporin for severe atopic dermatitis resulted in a favorable subjective and objective clinical response and the measurement of blood concentration mostly correlated with the effective dosage assessment.


Assuntos
Ciclosporina/administração & dosagem , Dermatite Atópica/tratamento farmacológico , Imunossupressores/administração & dosagem , Adulto , Área Sob a Curva , Ciclosporina/sangue , Ciclosporina/farmacocinética , Monitoramento de Medicamentos , Feminino , Humanos , Imunossupressores/sangue , Imunossupressores/farmacocinética , Masculino , Fatores de Tempo
19.
Am J Dermatopathol ; 34(3): 287-91, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22207446

RESUMO

We describe 2 cases of male nipple leiomyoma. A 70-year-old man had a painful subcutaneous tumor on his left nipple of 6 months duration. Histopathology disclosed dermal spindle cells with oval-shaped nuclei forming interlacing bundles with irregular pattern. Glandular elements were absent. The spindle cells were positive to α-smooth muscle actin, desmin, and vimentin. Estrogen receptor (ER) and progesterone receptor (PrR) were negative. We diagnosed this case as male leiomyoma of the nipple. Another patient was a 61-year-old man with gynecomastia induced by spironolactone of 6 months duration. He also had a painful nodule on his left nipple and histopathology disclosed spindle-shaped tumor cells as in the previous patient. The tumor was accompanied by glandular elements in the deep dermis and subcutaneous tissue, which showed apocrine secretion and were positive for α-smooth muscle actin, ER, and PrR. These glandular elements were interpreted as mammary gland. But ER and PrR stain did not show positive results for leiomyoma in the upper dermis. To the best of our knowledge, this is the first report of male idiopathic and gynecomastia-induced leiomyoma with ER and PrR staining.


Assuntos
Neoplasias da Mama Masculina/diagnóstico , Ginecomastia/patologia , Leiomioma/diagnóstico , Mamilos/patologia , Actinas/metabolismo , Idoso , Neoplasias da Mama Masculina/metabolismo , Desmina/metabolismo , Ginecomastia/induzido quimicamente , Ginecomastia/metabolismo , Humanos , Leiomioma/metabolismo , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/efeitos adversos , Mamilos/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Espironolactona/efeitos adversos
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