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1.
Dalton Trans ; 52(39): 13895-13905, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37656432

RESUMO

Perovskite-type oxynitrides have recently been highlighted due to their dielectric and photocatalytic properties. Numerous studies have addressed the synthesis and characterization of their nanocrystals and ceramics. However, few research works have considered single-crystal formation in such systems due to difficulties in melt growth. In this study, we explore the crystal growth of perovskite-type oxynitride SrTaO2N by an NH3-assisted SrCl2 flux method. Submillimeter-sized single crystals with lengths of approximately 300 µm were grown at a temperature of 1200 °C for 10 h with a solute concentration of 1.5 mol%. Subsequently, the crystal growth mechanism of SrTaO2N in an SrCl2 flux was studied systematically through experiments with variable holding temperature, holding time, cooling rate, and solute concentration. Our results suggest that SrTaO2N crystal growth is induced by the evaporation of SrCl2 flux.

2.
Front Neurol ; 14: 1212024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602264

RESUMO

Background and purpose: Non-invasive, simple, and repetitive swallowing evaluation is required to prevent aspiration pneumonia in neurological care. We investigated the usefulness of swallowing sound evaluation in patients with amyotrophic lateral sclerosis (ALS) using our new electronic stethoscope artificial intelligence (AI) analysis tool. Methods: We studied patients with ALS who provided written informed consent. We used an electronic stethoscope, placed a Bluetooth-enabled electronic stethoscope on the upper end of the sternum, performed a 3-mL water swallow three times, and remotely identified the intermittent sound components of the water flow caused at that time by AI, with the maximum value as the swallowing sound index. We examined the correlation between the swallowing sound index and patient background, including swallowing-related parameters. Results: We evaluated 24 patients with ALS (age 64.0 ± 11.8 years, 13 women, median duration of illness 17.5 months). The median ALS Functional Rating Scale-Revised (ALSFRS-R) score was 41 (minimum 18, maximum 47). In all cases, the mean swallowing sound index was 0.209 ± 0.088. A multivariate analysis showed that a decrease in the swallowing sound index was significantly associated with a low ALSFRS-R score, an ALSFRS-R bulbar symptom score, % vital capacity, tongue pressure, a Mann Assessment of Swallowing Ability (MASA) score, and a MASA pharyngeal phase-related score. Conclusion: Swallowing sound evaluation using an electronic stethoscope AI analysis showed a correlation with existing indicators in swallowing evaluation in ALS and suggested its usefulness as a new method. This is expected to be a useful examination method in home and remote medical care.

3.
Genome Biol Evol ; 15(3)2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36799928

RESUMO

Species phylogenetic trees represent the evolutionary processes of organisms, and they are fundamental in evolutionary research. Therefore, new methods have been developed to obtain more reliable species phylogenetic trees. A highly reliable method is the construction of an ortholog data set based on sequence information of genes, which is then used to infer the species phylogenetic tree. However, although methods for constructing an ortholog data set for species phylogenetic analysis have been developed, they cannot remove some paralogs, which is necessary for reliable species phylogenetic inference. To address the limitations of current methods, we developed OrthoPhy, a program that excludes paralogs and constructs highly accurate ortholog data sets using taxonomic information dividing analyzed species into monophyletic groups. OrthoPhy can remove paralogs, detecting inconsistencies between taxonomic information and phylogenetic trees of candidate ortholog groups clustered by sequence similarity. Performance tests using evolutionary simulated sequences and real sequences of 40 bacteria revealed that the precision of ortholog inference by OrthoPhy is higher than that of existing programs. Additionally, the phylogenetic analysis of species was more accurate when performed using ortholog data sets constructed by OrthoPhy than that performed using data sets constructed by existing programs. Furthermore, we performed a benchmark test of the Quest for Orthologs using real sequence data and found that the concordance rate between the phylogenetic trees of orthologs inferred by OrthoPhy and those of species was higher than the rates obtained by other ortholog inference programs. Therefore, ortholog data sets constructed using OrthoPhy enabled a more accurate phylogenetic analysis of species than those constructed using the existing programs, and OrthoPhy can be used for the phylogenetic analysis of species even for distantly related species that have experienced many evolutionary events.


Assuntos
Evolução Biológica , Filogenia
4.
Anal Sci ; 39(2): 203-211, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36441475

RESUMO

We present a lossy mode resonance (LMR) sensor fabricated by chemical bath deposition (CBD) using a U-shaped optical fiber with an exposed core. The ZnO particles that generate LMR were prepared by a very costly method in three steps via permanganate activation and the deposition of ZnO on the fiber core using CBD. The process of deposition was monitored in real time through the optical fiber, and a clear absorption spectrum with an LMR peak was obtained. The surface of the sensor with absorbance reaching 1.0 was covered with nano- to submicron particles of ZnO. The refractive index (RI) sensitivity of the sensor was measured using sucrose solution and was found to increase as the amounts of ZnO on the sensor increased, reaching 23 Abs/RI unit (RIU). The RI resolutions of the sensors with absorbance reaching 0.40, 0.65, and 1.0 during CBD were determined as ΔRI = 0.000060, 0.00017, and 0.00018, respectively, with a 99.7% confidence interval for the RI. Pretreatment during CBD was found to dramatically affect the fabrication of LMR sensors owing to their size and occupancy of deposited ZnO particles, the effects of which can be observed in real time using fiber optics.

5.
J Hum Genet ; 68(2): 91-95, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336708

RESUMO

Facioscapulohumeral dystrophy type1 (FSHD1) patients with a shortened D4Z4 repeat containing the DUX4 gene have a broad spectrum of clinical manifestations. In addition, high expression of DUX4 protein with an aberrant C terminus is frequently identified in B cell acute lymphoblastic leukemia. We investigated clinical manifestations in 31 FSHD1 patients and 30 non-affected individuals. Gastrointestinal cancers (gastric and colorectal cancers) increased after the age of 40 years and were more frequently observed in FSHD1 patients (n = 10) than in non-affected individuals (n = 2, p = 0.0217), though the incidence of cancers occurring in non-gastrointestinal tissues of FSHD1 patients was the same as that of non-affected individuals (p > 0.999). These comorbidities of FSHD1 patients were not associated with D4Z4 repeat number. Our results suggest that gastrointestinal cancers are among the extramuscular manifestations of adult FSHD1 patients, and do not depend on D4Z4 repeat number.


Assuntos
Neoplasias Gastrointestinais , Distrofia Muscular Facioescapuloumeral , Adulto , Humanos , Proteínas Cromossômicas não Histona/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Distrofia Muscular Facioescapuloumeral/epidemiologia , Distrofia Muscular Facioescapuloumeral/genética , Distrofia Muscular Facioescapuloumeral/metabolismo , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/genética
6.
Intern Med ; 62(12): 1835-1842, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36351577

RESUMO

Cryptogenic new-onset refractory status epilepticus (C-NORSE) is a neurologic emergency condition characterized by refractory status epilepticus (RSE) of unknown cause. Brain atrophy in a setting of C-NORSE is usually irreversible. A 33-year-old woman who was highly suspected of C-NORSE once showed mild frontotemporal atrophy on brain magnetic resonance imaging (MRI), but follow-up MRI revealed recovery of the brain atrophy. Her cognitive function also gradually improved, with a reduction in seizure frequency. Early initiation of intensive immunotherapy with anti-seizure medications may have minimized irreversible brain damage associated with RSE, resulting in a relatively good outcome.


Assuntos
Doenças do Sistema Nervoso Central , Doenças Neurodegenerativas , Estado Epiléptico , Feminino , Humanos , Adulto , Encéfalo/diagnóstico por imagem , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/etiologia , Doenças do Sistema Nervoso Central/complicações , Doenças Neurodegenerativas/complicações , Imageamento por Ressonância Magnética/efeitos adversos
7.
Anal Sci ; 38(12): 1549-1554, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36152169

RESUMO

Fiber optic sensors for monitoring scale deposition in geothermal brine and hot spring water should be safe, easily fabricated, and readily disposable. These desired features already have been enhanced in plastic optical fibers (POFs) and U-shaped sensors for other applications. The present work reports a U-shaped POF sensor for CaCO3 scale deposition. The sensors were easily fabricated by thermally bending the bulk POF without removing the cladding. At the bend, the percentage of total internal reflection between the water and the POF surface is affected by the high refractive index of the CaCO3 deposit. The optical responses of the U-shaped sensor to CaCO3 formation were investigated in a mixture of calcium chloride dehydrate and sodium hydrogen carbonate using a white-light source and a spectroscopic detector. The sensor was responsive to CaCO3 formation on the sensor surface and was especially sensitive at small bending radii. The sensitivity was further enhanced by increasing the number of bends. Finally, the U-shaped POF sensor was applied to the monitoring of CaCO3 scale deposition in hot spring water sampled at Matsushiro, Japan.


Assuntos
Fontes Termais , Fibras Ópticas , Plásticos/química , Água , Tecnologia de Fibra Óptica
9.
Nature ; 598(7880): 304-307, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34433207

RESUMO

The unprecedented impact of human activity on Earth's climate and the ongoing increase in global energy demand have made the development of carbon-neutral energy sources ever more important. Hydrogen is an attractive and versatile energy carrier (and important and widely used chemical) obtainable from water through photocatalysis using sunlight, and through electrolysis driven by solar or wind energy1,2. The most efficient solar hydrogen production schemes, which couple solar cells to electrolysis systems, reach solar-to-hydrogen (STH) energy conversion efficiencies of 30% at a laboratory scale3. Photocatalytic water splitting reaches notably lower conversion efficiencies of only around 1%, but the system design is much simpler and cheaper and more amenable to scale-up1,2-provided the moist, stoichiometric hydrogen and oxygen product mixture can be handled safely in a field environment and the hydrogen recovered. Extending our earlier demonstration of a 1-m2 panel reactor system based on a modified, aluminium-doped strontium titanate particulate photocatalyst4, we here report safe operation of a 100-m2 array of panel reactors over several months with autonomous recovery of hydrogen from the moist gas product mixture using a commercial polyimide membrane5. The system, optimized for safety and durability, and remaining undamaged on intentional ignition of recovered hydrogen, reaches a maximum STH of 0.76%. While the hydrogen production is inefficient and energy negative overall, our findings demonstrate that safe, large-scale photocatalytic water splitting, and gas collection and separation are possible. To make the technology economically viable and practically useful, essential next steps are reactor and process optimization to substantially reduce costs and improve STH efficiency, photocatalyst stability and gas separation efficiency.

10.
Biology (Basel) ; 10(4)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33920032

RESUMO

Nitrogen fixation plays a crucial role in the nitrogen cycle by helping to convert nitrogen into a form usable by other organisms. Bacteria capable of fixing nitrogen are found in six phyla including Cyanobacteria. Molybdenum dependent nitrogenase (nif) genes are thought to share a single origin as they have homologs in various phyla. However, diazotrophic bacteria have a mosaic distribution within the cyanobacterial lineage. Therefore, the aim of this study was to determine the cause of this mosaic distribution. We identified nif gene operon structures in the genomes of 85 of the 179 cyanobacterial strains for which whole genome sequences were available. Four nif operons were conserved in each diazotroph Cyanobacterium, although there were some gene translocations and insertions. Phylogenetic inference of these genes did not reveal horizontal gene transfer from outside the phylum Cyanobacteria. These results support the hypothesis that the mosaic distribution of diazotrophic bacteria in the cyanobacterial lineage is the result of the independent loss of nif genes inherited from common cyanobacterial ancestors in each lineage.

11.
Anal Chem ; 92(14): 9714-9721, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32551577

RESUMO

We present an electrochemical long period fiber grating (LPFG) sensor for electroactive species with an optically transparent electrode. The sensor was fabricated by coating indium tin oxide onto the surface of LPFG using a polygonal barrel-sputtering method. LPFG was produced by an electric arc-induced technique. The sensing is based on change in the detection of electron density on the electrode surface during potential application and its reduction by electrochemical redox of analytes. Four typical electroactive species of methylene blue, hexaammineruthenium(III), ferrocyanide, and ferrocenedimethanol were used to investigate the sensor performance. The concentrations of analytes were determined by the modulation of the potential as the change in transmittance around the resonance band of LPFG. The sensitivity of the sensor, particularly to methylene blue, was high, and the sensor responded to a wide concentration range of 0.001 mM to 1 mM.

12.
Sensors (Basel) ; 20(10)2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32423008

RESUMO

Herein, we propose an evanescent-wave fiber optic sensing technique for the anionic dye uranine based on ion association extraction. The sensor was prepared by removing a section of the cladding from a multimode fiber and hydrophobization of the exposed core surface. Uranine was extracted in association along with hexadecyltrimethylammonium (CTA) ion onto the fiber surface and detected via absorption of the evanescent wave generated on the surface of the exposed fiber core. The effect of CTA+ concentration added for ion association was investigated, revealing that the absorbance of uranine increased with increasing CTA+ concentration. A change in the sensor response as a function of the added uranine concentration was clearly observed. The extraction data were analyzed using a distribution equilibrium model and a Freundlich isotherm. The uranine concentration in the evanescent field of the fiber optic was up to 54 times higher than that in the bulk solution, and the limit of detection (3σ) for uranine was found to be 1.3 nM.

13.
Anal Sci ; 36(5): 561-565, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32147632

RESUMO

A certified reference material, NIMD-01, was developed for the analysis of mercury speciation in human hair. We collected the hair of Vietnamese males from a barbershop in Hanoi in 2016 and prepared 1200 bottles containing 3 g of sieved and blended hair powder. The certified value was given on a dry-mass basis, with the moisture content obtained by drying at 85°C for 4 h. Certified values with the expanded uncertainties (coverage factor, k = 2) were as follows: methylmercury, 0.634 ± 0.071 mg kg-1 as mercury; total mercury, 0.794 ± 0.050 mg kg-1; copper, 12.8 ± 1.4 mg kg-1; zinc, 234 ± 29 mg kg-1; selenium, 1.52 ± 0.29 mg kg-1. An indicative arsenic concentration of 0.17 ± 0.03 mg kg-1 was measured. Extended uncertainties were estimated by sample homogeneity, long- and short-term stabilities, and a characterization from measurements made by collaborating laboratories.


Assuntos
Cabelo/química , Compostos de Metilmercúrio/análise , Humanos , Masculino , Vietnã
14.
Sci Rep ; 9(1): 10719, 2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31341197

RESUMO

Treatment with an electromagnetic field, one of the potential techniques to inhibit scale deposition from water, has the advantage of not requiring the addition of any chemicals. Field tests using a fibre optic sensor were conducted to evaluate the effect that the treatment of hot spring water in Matsushiro, Japan with an electromagnetic field had on calcium carbonate scale formation. The optical response to scale deposition recorded by the fibre optic sensor decreased as a consequence of the application of an electromagnetic field, and the effectiveness of scale formation inhibition depended on the frequency of the electromagnetic field. This evidence was compared with results from changes in scale mass measured using the quartz crystal microbalance (QCM) method. Mass increases of the scale formed on the quartz crystal surface in hot spring water were inhibited by electromagnetic field treatment. These results were verified performing a column flow test, whereby the flow rate of hot spring water through a column was measured.

15.
Nat Mater ; 18(8): 827-832, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31209390

RESUMO

Oxysulfide semiconductors have narrow bandgaps suitable for water splitting under visible-light irradiation, because the electronegative sulfide ions negatively shift the valence band edges of the corresponding oxides1,2. However, the instability of sulfide ions during the water oxidation is a critical obstacle to simultaneous evolution of hydrogen and oxygen3. Here, we demonstrate the activation and stabilization of Y2Ti2O5S2, with a bandgap of 1.9 eV, as a photocatalyst for overall water splitting. On loading of IrO2 and Rh/Cr2O3 as oxygen and hydrogen evolution co-catalysts, respectively, and fine-tuning of the reaction conditions, simultaneous production of stoichiometric amounts of hydrogen and oxygen was achieved on Y2Ti2O5S2 during a 20 h reaction. The discovery of the overall water splitting capabilities of Y2Ti2O5S2 extends the range of promising materials for solar hydrogen production.

16.
J Insect Sci ; 18(6)2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30535416

RESUMO

Odorant coreceptor (Orco) represents one of the essential genes in the insect olfactory system, which facilitates signal transduction and heterodimerization with different odorant receptors (Ors) in the insect antennal dendritic membrane. Evolutionary analysis by detecting positive selection is important to examine the functional flexibility of Orco that potentially supports insect survival. The maximum likelihood codon substitution model was applied using CODEML program as implemented in PAML ver 4.9e package across 59 Orco codon sequences available from GenBank. These sequences represented five major insect orders and two reproductive systems (holometabola and nonholometabola). In the site model that identified common ω values for Orco, it was clearly shown that Orco was under strong purifying selection, indicated by the ω value that was far from 1 (ω: 0.03). However, in to the branch model, positive selection was detected to be acting on Dipteran lineages, whereas in the branch-site model, several sites were under significant positive selection occurring in the following four clades: Coleoptera, Diptera, Lepidoptera, and Psocodea. The typical evolutionary mode acting on Orco was consistent with the entropy value [H(x)], confirming that 48.9% of the Orco site was under conservation (H(x) < 0.5), whereas 26.9% of the Orco sites was under high variation (H(x) > 1). These findings confirmed that Orco genes are generally highly conserved and can possibly be used for the manipulation of insect pest control programs. However, positive selection that acts on certain lineages suggested future adaptive evolutionary ability of Orco to anticipate flexible functions for successful olfactory processes.


Assuntos
Evolução Molecular , Insetos/classificação , Insetos/genética , Receptores Odorantes/metabolismo , Seleção Genética , Animais , Sequência Conservada , Receptores Odorantes/genética
17.
Water Sci Technol ; 2017(3): 782-790, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30016296

RESUMO

Thermal conversion of sewage sludge can be a clean source of renewable energy if the emission of air pollutants from the source is controlled. In 2013, the Minamata Convention on Mercury was adopted, placing greater emphasis on the control of mercury emissions, including mercury emissions from sewage sludge incinerators. To characterise the behaviour of mercury in flue gas, particulate and gaseous mercury concentrations in two incinerators and a melting furnace were measured by manual sampling. In a third facility, continuous emission monitoring was used to characterise temporal trends in gaseous mercury concentrations. Wet scrubbers were determined to be effective air pollution control devices suitable for mercury removal. Stack mercury concentrations were found to be <10 µg/Nm3, which meets the mercury emission standard for existing plants (50 µg/Nm3).


Assuntos
Poluentes Atmosféricos/química , Incineração , Mercúrio/química , Esgotos/química , Poluição do Ar , Carvão Mineral , Monitoramento Ambiental , Gases
18.
BMC Neurol ; 18(1): 36, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29625555

RESUMO

BACKGROUND: Transient global amnesia is reported to be caused by cerebral venous congestion. Internal jugular venous flow reversal in particular with the Valsalva maneuver leads to cerebral venous congestion. In addition, Valsalva maneuver can also induce subarachnoid hemorrhage. Transient global amnesia and subarachnoid hemorrhage might have common a pathophysiology in cerebral venous congestion. CASE PRESENTATION: We report here the case of a 57-year-old woman who twice experienced convexal subarachnoid hemorrhage just after straining at stool following an episode of transient global amnesia. Digital subtraction angiography showed left temporal congestion. Left jugular vein ultrasonography revealed reflux with the Valsalva maneuver only in acute phase, indicating transient cerebral venous congestion. CONCLUSIONS: Subarachnoid hemorrhage followed by transient global amnesia indicates a common factor between them. Transient venous congestion is discussed in order to explain this rare phenomenon.


Assuntos
Amnésia Global Transitória , Veias Cerebrais/fisiopatologia , Hemorragia Subaracnóidea , Defecação , Feminino , Humanos , Pessoa de Meia-Idade , Manobra de Valsalva
19.
Colloids Surf B Biointerfaces ; 145: 285-290, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27208442

RESUMO

Titanium (Ti) treated with NaOH and hot water, and heated in an ammmonia (NH3) gas atmosphere for 1 or 3h exhibited in vitro apatite formation within 7days when soaked in simulated body fluid (SBF). Moreover, the treated Ti decomposed methylene blue and showed excellent bactericidal activity against Escherichia coli under visible light irradiation. The surface treatment resulted in the formation of a fine network of N-doped anatase-type titania (TiO2-xNx) on the Ti surface, which was responsible for both the apatite formation in SBF and the visible light-induced antibacterial activity. These preliminary results highlight the efficacy of our simple method for producing novel bioactive Ti with visible light-induced antibacterial activity, which could be applied to orthopaedic and dental implants without the risk of infection.


Assuntos
Amônia/farmacologia , Antibacterianos/farmacologia , Temperatura Alta , Luz , Nitrogênio/farmacologia , Hidróxido de Sódio/farmacologia , Titânio/farmacologia , Água/farmacologia , Apatitas/química , Atmosfera , Catálise/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Espectroscopia Fotoeletrônica , Propriedades de Superfície , Difração de Raios X
20.
Nanotechnology ; 23(2): 025702, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22166589

RESUMO

Defect mediated high temperature ferromagnetism in oxide nanocrystallites is the central feature of this work. Here, we report the development of room temperature ferromagnetism in nanosized Co-doped barium titanate particles with a size of around 14 nm, synthesized by a solvothermal drying method. A combination of x-ray diffraction with state-of-the-art electron microscopy techniques confirms the intrinsic doping of Co into BaTiO3. The development of the room temperature ferromagnetism was tracked down to the different donor defects, namely hydroxyl groups at the oxygen site (OH·(O) and oxygen vacancies (V··(O), and their relative concentrations at the surface and the core of the nanocrystal, which could be controlled by post-synthesis drying and thermal treatments.

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