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1.
Int J Legal Med ; 135(1): 301-305, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32474665

RESUMEN

We report a suicide case of complete decapitation using a self-constructed guillotine. A 45-year-old man, whose body was severely burned, was found dead. The head was completely separated from the middle level of the neck, and a sharp blade with a steel frame was placed between the head and neck. The severance plane passed between the C4 and C5 vertebrae. Vital reactions such as hemorrhage could not be confirmed at the decapitated skin edge because the body was severely burned. Both common carotid arteries were sharply transected. Subendocardial hemorrhage was detected in the left ventricle. Only a little blood, but no soot, was detected in the respiratory tract, including the trachea and bilateral bronchi. Subarachnoid hemorrhage was noted at the edge of the cervical spinal cord. The saturation level of CO-Hb was 5.7% in the left cardiac blood, 5.9% in the right cardiac blood, and 5.8% in the peripheral blood from the femoral vein. Cervical transection was diagnosed as the cause of death. We believe that he was unintentionally burned by spread fire from an automobile after decapitation by a self-constructed guillotine.


Asunto(s)
Quemaduras/patología , Decapitación , Suicidio Completo , Carboxihemoglobina/análisis , Traumatismos de las Arterias Carótidas/patología , Incendios , Ventrículos Cardíacos/patología , Hemorragia/patología , Humanos , Masculino , Persona de Mediana Edad , Sistema Respiratorio/patología , Hemorragia Subaracnoidea/patología
2.
Invest New Drugs ; 38(1): 140-147, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31289984

RESUMEN

Purpose We examined the feasibility, efficacy, and safety of TS-1 add-on therapy (TAT) in Japanese patients with triple-negative breast caner (TNBC). Methods TAT (TS-1, 80 mg/m2/day, BID, PO), consisting of the 21-day cycles of 14-day consecutive administration followed by 7-day drug holiday, was conducted for 365 days. The median follow-up was 75.2 months (range, 7.3-103.3 months). The primary endpoint was the feasibility of TAT. The secondary endpoints included relapse-free survival (RFS), overall survival (OS), and safety. Results 63 Japanese patients with TNBC (median age, 52.5 years; range, 23.7-68.6 years) were examined. Among them, 34 (54.0%) were postmenopausal, 54 (93.7%) had TNBC of common histological type, 51 (81.0%) had T1 to 3 tumors, 63 (100%) had undergone standardized surgery, and 44 (69.8%) and 19 (30.2%) had undergone neoadjuvant chemotherapy and adjuvant chemotherapy, respectively. The 365-day cumulative rate of TS-1 administration was 68.3% (95% confidence interval, 55.3-79.4), being comparable to 65.8% previously reported for gastric cancer. The 5-year RFS rates were 52.3% and 84.2% in the neoadjuvant and adjuvant chemotherapy groups, respectively, and the 5-year OS rates were 68.0% and 89.5%, respectively. The most common adverse events (AEs) were leucocyte count decreased (50.8%), total bilirubin decreased (44.4%), and pigmentation (42.9%). AEs were manageable clinically, and any grade 4 AEs did not develop. Conclusions The 365-day cumulative rate of TS-1 administration in TNBC patients was comparable to that in gastric cancer patients despite previous chemotherapy with anthracyclines and/or taxanes. TAT was feasible for TNBC patients after standard primary therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante/mortalidad , Terapia Neoadyuvante/mortalidad , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Adulto , Anciano , Docetaxel/administración & dosificación , Epirrubicina/administración & dosificación , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Pronóstico , Silicatos/administración & dosificación , Tasa de Supervivencia , Titanio/administración & dosificación , Neoplasias de la Mama Triple Negativas/patología
3.
Int J Legal Med ; 134(2): 597-601, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31792610

RESUMEN

Dendritic cells (DCs) can essentially contribute to innate and adaptive immune system in various organs. A double-color immunofluorescence analysis was carried out with anti-CD11c and -HLA-DRα antibodies to detect DCs in 53 skin wounds (their postinfliction intervals: group I, 0-3 days; group II, 4-7 days; group III, 9-14 days; and group IV, 17-21 days). CD11c+HLA-DRα+ DCs were first observed in skin wounds with postinfliction intervals of 3 days, and the DC numbers were found to be elevated in skin wounds with the subsequent increase in postinfliction intervals. Semi-quantitative morphometric analyses showed that the DC number was the highest in the 12-day-old wound. More than 50 DCs were present in 8 of 10 samples (80%) in group II and 14 of 16 samples (87.5%) in group III, and there was no difference between the two groups. Thus, the presence of DCs in a skin wound was possibly estimated as postinfliction intervals of at least 3 days. Furthermore, when a skin wound contained > 50 DCs, its age would be judged as 4-14 days. Collectively, the appearance of DCs in human skin wounds may provide useful information in determining the age of a wound.


Asunto(s)
Células Dendríticas , Patologia Forense , Piel/lesiones , Cicatrización de Heridas/inmunología , Adolescente , Adulto , Anciano , Antígeno CD11c , Niño , Técnica del Anticuerpo Fluorescente , Antígenos HLA-DR , Humanos , Persona de Mediana Edad , Traumatismos de los Tejidos Blandos/inmunología , Factores de Tiempo , Heridas Penetrantes/inmunología , Adulto Joven
4.
Int J Legal Med ; 134(3): 997-1002, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31836934

RESUMEN

This paper presents an unusual complex suicide case that died of nicotine addiction. The deceased was a 40-year-old male who was found lying dead on the floor in his room. In external findings, many incision wounds on his forearms and skin discoloration with epidermolysis on his cervical region could be seen. In the room, a blood-stained scissors and electric cord hanged on the exercise bike were found. Moreover, nine cigarette residues which were only the filter part and empty bottle of coffee were found on his side. At autopsy, we found that those injuries were not serious enough to lead him to the death. Toxicologically, caffeine, nicotine, cotinine, mirtazapine, and olanzapine could be detected, and the concentrations of nicotine were 3.740, 2.140, 3.100, and 451.100 µg/ml in cardiac blood, peripheral blood, urine, and stomach contents, respectively. These concentrations were evaluated as the fatal levels, and the cause of his death was diagnosed as acute nicotine intoxication.


Asunto(s)
Análisis Químico de la Sangre , Toxicología Forense , Contenido Digestivo/química , Nicotina/envenenamiento , Suicidio Completo , Adulto , Autopsia , Cafeína/análisis , Cotinina/análisis , Humanos , Masculino , Mirtazapina/análisis , Olanzapina/análisis
5.
Int J Legal Med ; 132(5): 1375-1380, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29356947

RESUMEN

In forensic practices, it is often difficult to determine wound vitality in compression marks of the neck with naked eyes. AQP1 and AQP3 are the major water channels associated with skin. Thus, we immunohistochemically examined the expression of AQP1 and AQP3 in neck skin samples to discuss their forensic applicability to determination of the wound vitality. Skin samples were obtained from 56 neck compression cases (hanging, 35 cases; strangulation, 21 cases). The intact skin from the same individual was taken as a control. Although AQP1 was immnunostained in dermal capillaries in both the neck compression marks and intact skin samples, there was no significant difference in the magnitude of AQP1 expression between both groups. On the contrary, AQP3-positive signals could be faintly detected in uninjured skin samples, and the positive signals seemed more intense in the keratinocytes in compression regions. Morphometrical analyses revealed that the ratio of AQP3-expressed keratinocytes was significantly enhanced in neck compression regions, compared with control groups. From the viewpoints of forensic pathology, immunohistochemical detection of AQP3 in the neck skin can be considered a valuable marker to diagnose the trace of antemortem compression.


Asunto(s)
Acuaporina 3/metabolismo , Acuaporinas/metabolismo , Patologia Forense , Piel/lesiones , Piel/metabolismo , Animales , Acuaporina 1/metabolismo , Asfixia , Humanos , Piel/citología
6.
Int J Legal Med ; 132(1): 237-242, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29080917

RESUMEN

Immunohistochemical investigation of aquaporin (AQP)1 and AQP3 was performed in human skin wounds obtained from forensic autopsy cases. A total of 55 human skin wounds of different postinfliction intervals were collected as follows: group I, 0-3 days (n = 16); II, 4-7 days (n = 11); III, 9-14 days (n = 16); and IV, 17-21 days (n = 12). In uninjured skin samples, AQP1 and AQP3 could be slightly detected in dermal vessels and keratinocytes, respectively. The percentage of AQP1+ vessels and the number of AQP3+ keratinocytes were apparently elevated in accordance with wound ages. The number of AQP3+ keratinocytes was distinctly evident in groups II and III. Morphometrically, both AQP1+ vessel area and AQP3+ cell number were markedly increased in group II, compared with other three groups. With regard to forensic safety, AQP1+ vessel area of over 5% would imply wound ages of 4-12 days. Moreover, the positive area of > 15% would suggest wound age of 7-10 days. Especially, most samples of skin wounds aged 5-10 days except for only one sample (a 10-day-old wound) showed AQP3+ cell number of > 300, and the remaining other samples had that of < 300. Thus, the AQP3+ cell number of > 300 would indicate wound ages of 5-10 days. Collectively, immunohistochemical analyses of AQP1 and AQP3 in human skin wounds would support the objective accuracy of wound age determination.


Asunto(s)
Acuaporina 1/metabolismo , Acuaporina 3/metabolismo , Piel/lesiones , Piel/metabolismo , Cicatrización de Heridas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Células , Niño , Patologia Forense , Humanos , Inmunohistoquímica , Queratinocitos/metabolismo , Persona de Mediana Edad , Piel/citología , Factores de Tiempo , Adulto Joven
7.
Breast Cancer Res Treat ; 157(2): 295-305, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27125669

RESUMEN

No clinical evidence on the efficacy and safety of eribulin monotherapy has been obtained by a prospective clinical study in patients with metastatic breast cancer (MBC) who had well-defined taxane resistance. The present Phase II, multicenter, single-arm, open-label study aimed to obtain the evidence. Japanese female patients, aged 33-74 years who had the metastasis of taxane-resistant and histopathologically confirmed breast cancer, received eribulin mesylate 1.4 mg/m(2) (equivalent to eribulin 1.23 mg/m(2) [expressed as free base]) as a 2- to 5-min intravenous infusion on days 1 and 8 of each 21-day cycle. The primary endpoint was the clinical benefit rate (CBR) [complete response (CR), partial response (PR), and long-term stable disease (LSD) ≥24 weeks]. A total of 51 patients underwent chemotherapy cycles (median 4; range 1-42 cycles). The CBR was 39.2 % (CR 2.0 %; PR 23.5 %; and LSD 13.7 %), and the rate of progressive disease was 49.0 %. The median progression-free survival and the median overall survival were 3.6 months [95 % confidence interval (CI) 2.6-4.6 months] and 11.7 months (95 % CI 9.2-14.2 months), respectively. Grade 3 or greater adverse events were leukopenia (23.5 %), neutropenia (35.3 %), anemia (5.9 %), and febrile neutropenia (7.8 %). The incidences of grade 3 and 4 peripheral sensory neuropathy were 2.0 and 0 %, respectively. Eribulin showed a clinically manageable tolerability profile by dose adjustments or symptomatic treatment. Eribulin was effective and well tolerated in heavily pretreated patients with MBC who had well-defined taxane resistance, thus providing a potential therapeutic option in the clinical settings.


Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Furanos/administración & dosificación , Cetonas/administración & dosificación , Adulto , Anciano , Antineoplásicos/efectos adversos , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Furanos/efectos adversos , Humanos , Infusiones Intravenosas , Japón , Cetonas/efectos adversos , Persona de Mediana Edad , Metástasis de la Neoplasia , Estudios Prospectivos , Análisis de Supervivencia , Resultado del Tratamiento
8.
Microscopy (Oxf) ; 73(2): 133-144, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38462986

RESUMEN

In-situ observation has expanded the application of transmission electron microscopy (TEM) and has made a significant contribution to materials research and development for energy, biomedical, quantum, etc. Recent technological developments related to in-situ TEM have empowered the incorporation of three-dimensional observation, which was previously considered incompatible. In this review article, we take up heating as the most commonly used external stimulus for in-situ TEM observation and overview recent in-situ TEM studies. Then, we focus on the electron tomography (ET) and in-situ heating combined observation by introducing the authors' recent research as an example. Assuming that in-situ heating observation is expanded from two dimensions to three dimensions using a conventional TEM apparatus and a commercially available in-situ heating specimen holder, the following in-situ heating-and-ET observation procedure is proposed: (i) use a rapid heating-and-cooling function of a micro-electro-mechanical system holder; (ii) heat and cool the specimen intermittently and (iii) acquire a tilt-series dataset when the specimen heating is stopped. This procedure is not too technically challenging and can have a wide range of applications. Essential technical points for a successful 4D (space and time) observation will be discussed through reviewing the authors' example application.

9.
Microscopy (Oxf) ; 72(2): 111-134, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36576339

RESUMEN

Electron tomography (ET) is a powerful tool for elucidating the properties and functionalities of materials. The innovative development of aberration-corrected electron microscopy in the early 21st century and the remarkable progress in the development of detectors, equipment and devices related to ET have resulted in substantial improvements in resolution. However, not only advances in hardware but also remarkable developments in reconstruction algorithms and related three-dimensional (3D) analysis methods have contributed to the resolution improvements. ET has its own problems, including the missing-wedge problem due to the limited tilt-angle range and the need to acquire numerous specimen-tilt images, the latter of which is time-consuming and can potentially damage the specimen. This review paper aims to (i) describe the established basic theories and definitions regarding 3D resolution of ET and practical 3D resolution measurement methods, (ii) discuss various reconstruction algorithms that effectively overcome the aforementioned problems and (iii) describe recent progress in the core of ET applications in materials science with respect to atomic ET, analytical ET and in-situ ET. The aforementioned ET problems have been addressed with each method developed in each field of application. Notably, in terms of aim (ii), recently developed reconstruction algorithms can reduce the number of projection images (specimen-tilt images) needed to attain a certain resolution without violating the Nyquist criterion. This approach is interpreted as a novel non-linear sampling theorem.

10.
Am J Case Rep ; 24: e940291, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37401051

RESUMEN

BACKGROUND Cardiac perforation is a rare complication of cardiac implantable electronic devices, with a reported incidence ranging from 0.1% to 5.2%. Delayed perforation, defined as perforation occurring more than 1 month after implantation, is more uncommon. In this report, we present a case of cardiac perforation involving the right ventricle wall that occurred 9 years after pacemaker implantation. CASE REPORT A 79-year-old woman presented with symptoms of dyspnea and was subsequently admitted to a hospital. She had undergone pacemaker implantation for a complete atrioventricular block 9 years prior to the presentation. The patient had right ventricular failure to capture and a resultant complete atrioventricular block. Computed tomography imaging revealed that the right ventricular lead had clearly protruded outside the heart; however, no pericardial effusion was observed. When the patient underwent open surgical repair, the ventricular tined lead was noted to be traversing the right ventricular apex. Device interrogation revealed a sudden increase followed by a gradual decrease in the right ventricular pacing threshold over the course of 2 months, indicating that the lead had slowly traversed the right ventricular muscle before ultimately rupturing through it. CONCLUSIONS This study described the case of a delayed right ventricular pacemaker lead perforation that occurred 9 years after implantation, which was managed via open surgical repair.


Asunto(s)
Bloqueo Atrioventricular , Lesiones Cardíacas , Marcapaso Artificial , Derrame Pericárdico , Femenino , Humanos , Anciano , Ventrículos Cardíacos/cirugía , Bloqueo Atrioventricular/terapia , Bloqueo Atrioventricular/complicaciones , Marcapaso Artificial/efectos adversos , Derrame Pericárdico/etiología , Lesiones Cardíacas/cirugía , Lesiones Cardíacas/complicaciones
11.
Nanoscale ; 15(23): 10133-10140, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37264793

RESUMEN

The nanoscale characterization of thermally activated solid reactions plays a pivotal role in products manufactured by nanotechnology. Recently, in situ observation in transmission electron microscopy combined with electron tomography, namely four-dimensional observation for heat treatment of nanomaterials, has attracted great interest. However, because most nanomaterials are highly reactive, i.e., oxidation during transfer and electron beam irradiation would likely cause fatal artefacts; it is challenging to perform the artifact-free four-dimensional observation. Herein, we demonstrate our development of a novel in situ three-dimensional electron microscopy technique for thermally activated solid-state reaction processes in nanoparticles (NPs). The sintering behaviour of Cu NPs was successfully visualized and analyzed in four-dimensional space-time. An advanced image processing protocol and a newly designed state-of-the-art MEMS-based heating holder enable the implementation of considerably low electron dose imaging and prevent air exposure, which is of central importance in this type of observation. The total amount of electron dose for a single set of tilt-series images was reduced to 250 e- nm-2, which is the lowest level for inorganic materials electron tomography experiments. This study evaluated the sintering behaviour of Cu NPs in terms of variations in neck growth and particle distance. A negative correlation between the two parameters is shown, except for the particle pair bound by neighbouring NPs. The nanoscale characteristic sintering behavior of neck growth was also captured in this study.


Asunto(s)
Tomografía con Microscopio Electrónico , Nanopartículas , Anaerobiosis , Microscopía Electrónica de Transmisión , Microscopía Electrónica
12.
Sci Rep ; 13(1): 6093, 2023 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-37055510

RESUMEN

Estimating time of death is one of the most important problems in forensics. Here, we evaluated the applicability, limitations and reliability of the developed biological clock-based method. We analyzed the expression of the clock genes, BMAL1 and NR1D1, in 318 dead hearts with defined time of death by real-time RT-PCR. For estimating the time of death, we chose two parameters, the NR1D1/BMAL1 ratio and BMAL1/NR1D1 ratio for morning and evening deaths, respectively. The NR1D1/BMAL1 ratio was significantly higher in morning deaths and the BMAL1/NR1D1 ratio was significantly higher in evening deaths. Sex, age, postmortem interval, and most causes of death had no significant effect on the two parameters, except for infants and the elderly, and severe brain injury. Although our method may not work in all cases, our method is useful for forensic practice in that it complements classical methods that are strongly influenced by the environment in which the corpse is placed. However, this method should be applied with caution in infants, the elderly, and patients with severe brain injury.


Asunto(s)
Factores de Transcripción ARNTL , Lesiones Encefálicas , Lactante , Humanos , Anciano , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Reproducibilidad de los Resultados , Relojes Biológicos/genética , Autopsia , Ritmo Circadiano/genética
13.
Nat Astron ; 7(2): 170-181, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36845884

RESUMEN

Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe3+ to Fe2+ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (-OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss.

14.
Front Med (Lausanne) ; 9: 867365, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35492347

RESUMEN

Ubiquitin is a member of the heat shock protein family and is rapidly induced by various types of stimuli, including ischemic and mechanical stress. However, its significance in determining wound vitality of neck compression skin in forensic pathology remains unclear. We immunohistochemically examined the expression of ubiquitin in the neck skin samples to understand its forensic applicability in determining wound vitality. Skin samples were obtained from 53 cases of neck compression (hanging, 42 cases; strangulation, 11 cases) during forensic autopsies. Intact skin from the same individual was used as the control. Ubiquitin expression was detected in 73.9% of keratinocytes in intact skin samples, but only in 21.2% of keratinocytes in the compression regions, with statistical differences between the control and compression groups. This depletion in the case of neck compression may be caused by the impaired conversion of conjugated to free ubiquitin and failure of de novo ubiquitin synthesis. From a forensic pathological perspective, immunohistochemical examination of ubiquitin expression in the skin of the neck can be regarded as a valuable marker for diagnosing traces of antemortem compression.

15.
Leg Med (Tokyo) ; 54: 101989, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34798589

RESUMEN

Here, we report a case of necrotizing fasciitis following intra-articular injection of hyaluronic acid. A 73-year-old female received intra-articular injections of hyaluronic acid due to arthralgia at the left shoulder and knee, and was found dead in her living room at one day. At the forensic autopsy, injection marks with bullae and erythema were found at the left shoulder and knee and liquefactive necrosis of muscle tissues was observed in the left but not right extremities. Histopathological examinations of the left upper arm and thigh revealed severe rhabdomyolysis with lots of bacterial clusters. Bacteriological examinations detected group A Streptococcus from intracardiac blood and affected muscle tissues. Postmortem biochemical analysis of blood showed escalated blood urea nitrogen (133.8 mg/dL), creatinine (4.57 mg/dL) and C-reactive protein (45.0 mg/dL). The cause of her death was diagnosed as streptococcal toxic shock syndrome (STSS). Moreover, it was suggested that the injection was inappropriately conducted and served as a portal of bacterial entry.


Asunto(s)
Fascitis Necrotizante , Infecciones Estreptocócicas , Anciano , Fascitis Necrotizante/etiología , Femenino , Humanos , Enfermedad Iatrogénica , Inyecciones Intraarticulares , Streptococcus pyogenes
16.
Microsc Microanal ; 17(6): 983-90, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22030303

RESUMEN

Focused ion beam (FIB) induced damage in nanocrystalline Al thin films has been characterized using advanced transmission electron microscopy techniques. Electron tomography was used to analyze the three-dimensional distribution of point defect clusters induced by FIB milling, as well as their interaction with preexisting dislocations generated by internal stresses in the Al films. The atomic structure of interstitial Frank loops induced by irradiation, as well as the core structure of Frank dislocations, has been resolved with aberration-corrected high-resolution annular dark-field scanning TEM. The combination of both techniques constitutes a powerful tool for the study of the intrinsic structural properties of point defect clusters as well as the interaction of these defects with preexisting or deformation dislocations in irradiated bulk or nanostructured materials.


Asunto(s)
Aluminio/análisis , Microscopía Electrónica de Rastreo/métodos , Microscopía Electrónica de Transmisión/métodos , Nanoestructuras/análisis , Nanotecnología/métodos , Tomografía Computarizada por Rayos X/métodos , Cristalización , Iones , Micromanipulación , Dióxido de Silicio/química , Tomografía Computarizada por Rayos X/instrumentación
17.
Nanomaterials (Basel) ; 11(6)2021 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-34208185

RESUMEN

The temperature dependence thermal conductivity of the indium-gallium-zinc oxide (IGZO) thin films was investigated with the differential three-omega method for the clear demonstration of nanocrystallinity. The thin films were deposited on an alumina (α-Al2O3) substrate by direct current (DC) magnetron sputtering at different oxygen partial pressures ([PO2] = 0%, 10%, and 65%). Their thermal conductivities at room temperature were measured to be 1.65, 1.76, and 2.58 Wm-1K-1, respectively. The thermal conductivities decreased with an increase in the ambient measurement temperature. This thermal property is similar to that of crystalline materials. Electron microscopy observations revealed the presence of nanocrystals embedded in the amorphous matrix of the IGZO films. The typical size of the nanocrystals was approximately 2-5 nm with the lattice distance of about 0.24-0.26 nm. These experimental results indicate that the nanocrystalline microstructure controls the heat conduction in the IGZO films.

18.
Sci Rep ; 11(1): 20720, 2021 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-34702955

RESUMEN

Scanning transmission electron microscopy (STEM) is suitable for visualizing the inside of a relatively thick specimen than the conventional transmission electron microscopy, whose resolution is limited by the chromatic aberration of image forming lenses, and thus, the STEM mode has been employed frequently for computed electron tomography based three-dimensional (3D) structural characterization and combined with analytical methods such as annular dark field imaging or spectroscopies. However, the image quality of STEM is severely suffered by noise or artifacts especially when rapid imaging, in the order of millisecond per frame or faster, is pursued. Here we demonstrate a deep-learning-assisted rapid STEM tomography, which visualizes 3D dislocation arrangement only within five-second acquisition of all the tilt-series images even in a 300 nm thick steel specimen. The developed method offers a new platform for various in situ or operando 3D microanalyses in which dealing with relatively thick specimens or covering media like liquid cells are required.

19.
Sci Rep ; 11(1): 5636, 2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33707638

RESUMEN

The recent realisations of hydrogen doped LnFeAsO (Ln = Nd and Sm) superconducting epitaxial thin films call for further investigation of their structural and electrical transport properties. Here, we report on the microstructure of a NdFeAs(O,H) epitaxial thin film and its temperature, field, and orientation dependencies of the resistivity and the critical current density Jc. The superconducting transition temperature Tc is comparable to NdFeAs(O,F). Transmission electron microscopy investigation supported that hydrogen is homogenously substituted for oxygen. A high self-field Jc of over 10 MA/cm2 was recorded at 5 K, which is likely to be caused by a short London penetration depth. The anisotropic Ginzburg-Landau scaling for the angle dependence of Jc yielded temperature-dependent scaling parameters γJ that decreased from 1.6 at 30 K to 1.3 at 5 K. This is opposite to the behaviour of NdFeAs(O,F). Additionally, γJ of NdFeAs(O,H) is smaller than that of NdFeAs(O,F). Our results indicate that heavily electron doping by means of hydrogen substitution for oxygen in LnFeAsO is highly beneficial for achieving high Jc with low anisotropy without compromising Tc, which is favourable for high-field magnet applications.

20.
Influenza Other Respir Viruses ; 15(3): 389-395, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33099886

RESUMEN

BACKGROUND: Baloxavir marboxil (BXM) is an approved drug that selectively targets cap-dependent endonuclease on PA subunit in the RNA polymerase complex of influenza A and B viruses. Amino acid substitutions at position 38 in the PA subunit were identified as a major pathway for reduced susceptibility to baloxavir acid (BXA), the active form of BXM. Additionally, substitutions found at positions E23, A37, and E199 in the PA subunit impact BXA susceptibility by less than 10-fold. METHODS: We comprehensively evaluated the impact of novel amino acid substitutions identified in PA, PB1, and PB2 subunits in BXM clinical trials and influenza sequence databases by means of drug susceptibility and replicative capacity. RESULTS: PA/I38N in A(H1N1)pdm09 and PA/I38R in A(H3N2) were newly identified as treatment-emergent substitutions in the CAPSTONE-2 study. The I38N substitution conferred reduced susceptibility by 24-fold, whereas replicative capacity of the I38N-substituted virus was impaired compared with the wild-type. The I38R-substituted virus was not viable in cell culture. All other mutations assessed in this extensive study did not significantly affect BXA susceptibility (< 2.4-fold change). CONCLUSION: These results provide additional information on the impact of amino acid substitutions in the trimeric viral polymerase complex to BXA susceptibility and will further support influenza surveillance.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Humana , Sustitución de Aminoácidos , Antivirales/farmacología , Antivirales/uso terapéutico , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/uso terapéutico , Dibenzotiepinas , Farmacorresistencia Viral , Humanos , Subtipo H3N2 del Virus de la Influenza A , Virus de la Influenza A/genética , Gripe Humana/tratamiento farmacológico , Morfolinas/uso terapéutico , Piridonas/uso terapéutico , Triazinas
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