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Halide perovskites (HPs) are fascinating materials whose optoelectronic properties are arguably excitonic. In the HP family, biexcitons are known to exist only in low dimensions where exciton-exciton binding is strongly enhanced by quantum and dielectric confinements. In this paper, however, it is shown that they indeed do exist in 3D bulk CH3 NH3 PbBr3 (MAPbBr3 ) single crystals if the pristine crystal quality is ensured for subtle binding of two excitons. The existence of biexcitons is clearly evidenced below 30 K with a binding energy of ≈3.9 ± 0.3 meV according to i) exciton-biexciton population dynamics, ii) giant resonant two-photon excitation of biexcitons, iii) inverted Boltzmann-type spectral feature, and iv) zero degree of circular polarization in the biexciton photoluminescence. Because of the polariton effect, the two-photon resonance occurs at the excited biexciton state from which longitudinal-transverse splitting is calculated to be 3.7 meV. The discovery of the 3D biexcitons underscores the very quality of HP crystals for generating various many-body excitonic phases in MAPbBr3 and its analogues toward the improved understanding of their fundamental properties and highly efficient optoelectronic applications.
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Alloy formation is an advanced approach to improve desired properties that the monoelements cannot achieve. Alloys are usually designed to tailor intrinsic natures or induce synergistic effects by combining materials with distinct properties. Indeed, unprecedented properties have emerged in many cases, superior to a simple sum of pure elements. Here, we present Au-Ag alloy nanostructures with prominent catalytic properties in an electrochemical carbon dioxide reduction reaction (eCO2RR). The Au-Ag hollow nanocubes are prepared by galvanic replacement of Au on Ag nanocubes. When the Au-to-Ag ratio is 1:1 (Au1Ag1), the alloy hollow nanocubes exhibit maximum Faradaic efficiencies of CO production in a wide potential range and high mass activity and CO current density superior to those of the bare metals. In particular, overpotentials are estimated to be similar to or lower than that of the Au catalyst under various standard metrics. Density functional theory calculations, machine learning, and a statistical consideration demonstrate that the optimal configuration of the *COOH intermediate is a bidentate coordination structure where C binds to Au and O binds to Ag. This active Au-Ag neighboring configuration has a maximum population and enhanced intrinsic catalytic activity on the Au1Ag1 surface among other Au-to-Ag compositions, in good agreement with the experimental results. Further application of Au1Ag1 to a membrane electrode assembly cell at neutral conditions shows enhanced CO Faradaic efficiency and current densities compared to Au or Ag nanocubes, indicating the possible extension of Au-Ag alloys to larger electrochemical systems. These results give a new insight into the synergistic roles of Au and Ag in the eCO2RR and offer a fresh direction toward a rational design of bimetallic catalysts at a practical scale.
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Electrochemical CO2 reduction reaction (eCO2RR) has been considered one of the potential technologies to store electricity from renewable energy sources into chemical energy. For this aim, designing catalysts with high surface activities is critical for effective eCO2RR. In this study, we introduced a surface overgrowth method on stable Au icosahedrons to generate Au nanostars with large bumps. As a catalyst for eCO2RR, the Au nanostars exhibited a maximum faradaic efficiency (FE) of 98% and a mass activity of 138.9 A g-1 for CO production, where the latter was one of the highest activities among Au catalysts. Despite the deducted electrochemically active surface area per mass, the high-energy surfaces from overgrowth provided a 3.8-fold larger specific activity than the original Au icosahedral seeds, resulting in superior eCO2RR performances that outweigh the trade-off of size and shape in nanoparticles. The Au nanostars also represented prolonged stability due to the durability of high-energy facets. The characterization of surface morphology and density functional theory calculations revealed that predominant Au(321) facets on the Au nanostars effectively stabilized *COOH adsorbates, thus lowering the overpotential and improving the FE for CO production. This overgrowth method is simple and universal for various materials, which would be able to extend into a wide range of electrochemical catalysts.
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The retinal pigment epithelium (RPE) forms a monolayer sheet separating the retina and choroid in vertebrate eyes. The polarized nature of RPE is maintained by distributing membrane proteins differentially along apico-basal axis. We found the distributions of these proteins differ in embryonic, post-natal, and mature mouse RPE, suggesting developmental regulation of protein trafficking. Thus, we deleted tumor susceptibility gene 101 (Tsg101), a key component of endosomal sorting complexes required for transport (ESCRT), in embryonic and mature RPE to determine whether ESCRT-mediated endocytic protein trafficking correlated with the establishment and maintenance of RPE polarity. Loss of Tsg101 severely disturbed the polarity of RPE, which forms irregular aggregates exhibiting non-polarized distribution of cell adhesion proteins and activation of epidermal growth factor receptor signaling. These findings suggest that ESCRT-mediated protein trafficking is essential for the development and maintenance of RPE cell polarity.
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Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Células Epiteliais/metabolismo , Proteínas de Membrana/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Fatores de Transcrição/metabolismo , Animais , Polaridade Celular/fisiologia , Camundongos , Epitélio Pigmentado da Retina/citologiaRESUMO
Intussusception is a medical condition, in which a proximal part of the intestine folds into the distal intestine. Adult intussusceptions are rare and account for approximately 5% of all cases of intussusceptions. The anatomical leading points include tumors, diverticulums, polyps, and strictures in 80-90% of adult intussusceptions, and 65% of colon intussusceptions and 30% of small bowel intussusceptions originate from malignant tumors. Treatments for adult intussusception have not been established, but most cases require surgical treatment. The gastrointestinal tract is the most common extranodal site for non-Hodgkin lymphoma. The symptoms are mostly non-specific, but they rarely lead to complications, such as bleeding, perforation, and intussusception. Furthermore, few cases of primary gastrointestinal lymphomas causing intussusception have been reported. This paper reports a case of small bowel diffuse large B cell lymphoma that caused ileocolic intussusception in a 69-year-old woman with no medical history. She underwent a small bowel resection and received six cycles of adjuvant chemotherapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone. Since then, she has been in complete remission.
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Doenças do Íleo/diagnóstico , Intussuscepção/diagnóstico , Linfoma Difuso de Grandes Células B/patologia , Idoso , Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante , Endoscopia Gastrointestinal , Humanos , Doenças do Íleo/complicações , Íleo/patologia , Intussuscepção/complicações , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Tomografia Computadorizada por Raios XRESUMO
Conversion of carbon dioxide (CO2 ) into value-added chemicals has attracted much attention because it can not only resolve global warming issues by reducing CO2 accumulation in the atmosphere, but also produce renewable hydrocarbon fuels that are important feedstocks for the chemical industry. Among the diverse approaches reported, CO2 reduction via electro- and photocatalytic methods is at the center of topics due to potential engineering of reaction performance through rational design of catalyst features. In this Minireview, we highlight recent strategies for designing nanoparticles to maximize the reaction efficiency and selectivity; from a materials viewpoint, these strategies can provide critical information to guide future research directions.
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Malacoplasia/diagnóstico , Doenças do Colo Sigmoide/diagnóstico , Dor Abdominal/etiologia , Biópsia , Colo Sigmoide/diagnóstico por imagem , Colo Sigmoide/patologia , Pólipos do Colo/diagnóstico , Diagnóstico Diferencial , Hemorragia Gastrointestinal/etiologia , Humanos , Mucosa Intestinal/diagnóstico por imagem , Mucosa Intestinal/patologia , Malacoplasia/complicações , Malacoplasia/patologia , Masculino , Pessoa de Meia-Idade , Doenças do Colo Sigmoide/patologia , Sigmoidoscopia , Tomografia Computadorizada por Raios XRESUMO
Neutropenic enterocolitis is a fatal enterocolitis occurring in neutropenic patients with immunocompromised diseases including hematologic malignancies. Gastrointestinal (GI) mucormycosis in hematologic malignancies has been rarely reported. Especially, in myelodysplastic syndrome (MDS), GI mucormycosis has never been reported. We report a case of GI mucormocysis manifesting as neutropenic enterocolitis in a patient with MDS.
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BACKGROUND: Rectal neuroendocrine tumors (NETs) < 10 mm in diameter, limited to the submucosa without local or distant metastasis, can be treated endoscopically. Endoscopic mucosal resection with a ligation band device (EMR-L) and endoscopic submucosal dissection (ESD) have been employed to resect rectal NETs. We evaluated and compared the clinical outcomes of EMR-L and ESD for endoscopic resection of rectal NETs G1 < 10 mm in diameter. METHODS: We conducted a retrospective study of 82 rectal NETs in 82 patients who underwent either EMR-L or ESD. Therapeutic outcomes (en bloc resection and complete resection rates), procedure time, and procedure-related adverse events were evaluated. Additionally, we measured the distance of the lateral and vertical margins from the border of the tumor in pathologic specimens and compared the resectability between EMR-L and ESD. RESULTS: Sixty-six lesions were treated using EMR-L and 16 using ESD. En bloc resection was achieved in all patients. The complete resection rate with EMR-L was significantly higher than that with ESD (95.5% vs.75.0%, p = 0.025). The prevalence of vertical margin involvement was significantly higher in the ESD group than in the EMR-L group (12.5% vs. 0%, p = 0.036), and ESD was more time consuming than EMR-L (24.21 ± 12.18 vs. 7.05 ± 4.53 min, p < 0.001). The lateral and vertical margins were more distant in the EMR-L group than in the ESD group (lateral margin distance, 1661 ± 849 vs. 1514 ± 948 µm; vertical margin distance, 277 ± 308 vs. 202 ± 171 µm). CONCLUSIONS: EMR-L is more favorable for small rectal NETs with respect to therapeutic outcomes, procedure time, and technical difficulties. Additionally, EMR-L enables achievement of sufficient vertical margin distances.
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Duodenal neuroendocrine tumors (NETs) are rare, and risk factors associated with lymph node (LN) metastasis are still not well defined. The aim of this study was to investigate risk factors of LN metastasis in duodenal NETs based on the final histopathologic results and clinical follow-up data.This study included a total of 44 duodenal NETs in 38 patients who underwent endoscopic or surgical resection between January 2008 and December 2015. Diagnosis of duodenal NETs was confirmed based on immunohistochemical staining of chromogranin A, synaptophysin, and CD56; the clinicopathologic records were collected at the time of the initial diagnosis of duodenal NETs.Most duodenal NETs were small (≤1âcm in 33 tumors), World Health Organization (WHO) grade G1 (in 32 tumors), limited to the mucosa and/or submucosa (in 40 tumors), and located at the duodenal bulb (in 32 tumors). Of 44 tumors, lymphovascular invasion was present in 4 (9.1%), and among 38 patients, LN metastasis was detected in 4 (10.5%). LN metastases were significantly associated with the non-bulb location, tumor size >10âmm, tumor invasion into the muscularis propria or deeper, WHO grade G2, and lymphovascular invasion. During the mean follow-up period of 54.5 months (range, 24-123 months), recurrence occurred in 1 patient.Non-bulb location, tumor size >10âmm, invasion beyond the submucosa, WHO grade G2, and lymphovascular invasion are risk factors of LN metastasis in duodenal NETs. These findings can help clinicians choose the appropriate therapeutic modality for duodenal NETs.
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Neoplasias Duodenais/patologia , Metástase Linfática/patologia , Tumores Neuroendócrinos/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Fatores de Risco , Carga TumoralRESUMO
For long-term storage of renewable energy, the electrochemical carbon dioxide reduction reaction (CO2RR) offers a promising option for converting electricity to permanent forms of chemical energy. In this work, we present highly selective ethylene production dependent upon the catalyst morphology using copper oxide nanoparticles. The branched CuO nanoparticles were synthesized and then deposited on conductive carbon materials. After activation, the major copper species changed to Cu+, and the resulting electrocatalyst exhibited a high Faradaic efficiency (FE) of ethylene reaching over 70% and a hydrogen FE of 30% without any byproducts in a neutral aqueous solution. The catalyst also showed high durability (up to 12 h) with the ethylene FE over 65%. Compared to cubic morphology, the initial branched copper oxide structure formed highly active domains with interfaces and junctions in-between during activation, which caused large surface area with high local pH leading to high selectivity and activity for ethylene production.
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Do graphic pictorial health warnings (GPHWs) on cigarette packaging work better for some people than others? According to the Extended Parallel Process Model (EPPM), fear appeals should heighten positive change only if a person believes he or she is capable of change (i.e., self-efficacy). We exposed 242 smokers and 241 nonsmokers (aged 18-29) in the Republic of Korea to either a GPHW or a text-only warning in a between-subjects experiment. Results indicated that the GPHW increased intentions and motivations to quit smoking (for smokers) and intentions and motivations to not start smoking (for nonsmokers). However, these effects were moderated by self-efficacy related to quitting or not starting smoking. For smokers, a GPHW was especially effective in increasing desires and intentions to quit for people high in self-efficacy and high in self-esteem. However, for nonsmokers, a GPHW was effective only when self-efficacy was high, regardless of self-esteem level. For smokers and nonsmokers, results were mediated by heightened perceived health estimation. Implications for understanding the effectiveness of warning labels on cigarettes, for the introduction of GPHWs in the Republic of Korea, and for the Extended Parallel Process Model, are discussed.
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não Fumantes/estatística & dados numéricos , Rotulagem de Produtos/métodos , Autoimagem , Autoeficácia , Fumantes/estatística & dados numéricos , Produtos do Tabaco/efeitos adversos , Adolescente , Adulto , Atitude Frente a Saúde , Feminino , Humanos , Intenção , Masculino , Motivação , República da Coreia , Abandono do Hábito de Fumar/psicologia , Prevenção do Hábito de Fumar , Adulto JovemRESUMO
Although men typically hold favorable views of advertisements featuring female sexuality, from a Terror Management Theory perspective, this should be less the case when thoughts of human mortality are salient. Two experiments conducted in South Korea supported this hypothesis across a variety of products (e.g., perfume and vodka). Men became more negative towards advertisements featuring female sexuality, and had reduced purchase intentions for those products, after thinking about their own mortality. Study 2 found that these effects were mediated by heightened disgust. Mortality thoughts did not impact women in either study. These findings uniquely demonstrate that thoughts of death interact with female sex-appeal to influence men's consumer choices, and that disgust mediates these processes. Implications for the role of emotion, and cultural differences, in terror management, for attitudes toward female sexuality, and for marketing strategies are discussed.
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Strongly emissive cuprous complexes containing a stable σ-SiH-Cu motif were prepared. These complexes serve as a proof of principle that σ-complexation can be utilized as a design principle for engineering responsive light emitting materials. Their excited state lifetimes were found to be long (â¼20 µs) with high quantum yields (φ = 0.40-0.59).
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The antibacterial activities of the essential oil of Eucalyptus globulus (EOEG) was determined against 7 fish pathogenic bacteria (Edwardsiella tarda, Streptococcus iniae, S. parauberis, Lactococcus garviae, Vibrio harveyi, V. ichthyoenteri and Photobacterium damselae) obtained from farmed olive flounder. The inhibitory activity was evaluated by three methods: Disc diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). According to the disc diffusion test, as the concentration of EOEG (5-40 µg) rises, the inhibitory zone increases in size. Compared with amoxicillin, tetracycline and chloramphenicol, EOEG showed similar antibacterial activity. The MIC of EOEG ranged from 7.8 to 125 mg/mL and MBC values ranged from 62 to 250 mg/mL. These results show that EOEG has antimicrobial activity against all seven bacteria, but there was no marked difference between each genus. From these results, it is suggested that EOEG can be used as an antimicrobial agent against fish bacterial diseases in the fish industry.
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We presented a case of unusual endobronchial inflammatory polyps as a complication following endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in a patient with tuberculous lymphadenitis. EBUS-TBNA of the right hilar lymph node was performed in a 29-year-old, previously healthy man. The patient was confirmed with tuberculous lymphadenitis and received antituberculosis medication over the course of 6 months. Chest computed tomography, after 6 months of antituberculosis therapy following the EBUS-TBNA showed nodular bronchial wall thickening of the right main bronchus. Histological and microbiological examinations revealed inflammatory polyps. After 7 months, the inflammatory polyps regressed almost completely without need for removal.
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Natural variation in heading-date genes enables rice, a short-day (SD) plant, to flower early under long-day (LD) conditions at high latitudes. Through analysis of heading-date quantitative trait loci (QTL) with F7 recombinant inbred lines from the cross of early heading 'H143' and late heading 'Milyang23 (M23)', we found a minor-effect Early Heading3 (EH3) QTL in the Hd16 region on chromosome 3. We found that Early flowering1 (EL1), encoding casein kinase I (CKI), is likely to be responsible for the EH3/Hd16 QTL, because a missense mutation occurred in the highly conserved serine/threonine kinase domain of EL1 in H143. A different missense mutation was found in the EL1 kinase domain in Koshihikari. In vitro kinase assays revealed that EL1/CKI in H143 and Koshihikari are non-functional. In F7:9 heterogeneous inbred family-near isogenic lines (HNILs), HNIL(H143) flowered 13 days earlier than HNIL(M23) in LD, but not in SD, in which EL1 mainly acts as a LD-dependent flowering repressor, down-regulating Ehd1 expression. In the world rice collection, two types of non-functional EL1 variants were found in japonica rice generally cultivated at high latitudes. These results indicate that natural variation in EL1 contributes to early heading for rice adaptation to LD in temperate and cooler regions.
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Caseína Quinase I/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Variação Genética , Oryza/genética , Locos de Características Quantitativas/genética , Alelos , Caseína Quinase I/metabolismo , Mapeamento Cromossômico , Regulação para Baixo , Flores/genética , Flores/efeitos da radiação , Geografia , Endogamia , Mutação de Sentido Incorreto , Oryza/fisiologia , Oryza/efeitos da radiação , Fosforilação , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , TemperaturaRESUMO
Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using whole-genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 (OsPRR37; hereafter PRR37) is responsible for the Early heading7-2 (EH7-2)/Heading date2 (Hd2) QTL which was identified from a cross of late-heading rice 'Milyang23 (M23)' and early-heading rice 'H143'. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT (CONSTANS, CO-like, and TOC1) domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day conditions, and are adapted to the northernmost regions of rice cultivation, up to 53° N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and Ghd7/Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions.
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Variação Genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Alelos , Mutação de Sentido Incorreto , Oryza/genética , Locos de Características QuantitativasRESUMO
A novel solvatochromic fluorescent molecule, 9,9-dibutyl-7-(dimethylamino)-2-fluorenesulfonate 2 was synthesized from 2-nitrofluorene in moderate yield. The fluorescence spectra of 2 and 7-(dimethylamino)-2-fluorenesulfonate 1 shift to shorter wavelengths as the polarity of the medium decreases. Both 1 and 2 bind to hydrophobic sites of human serum albumin (HSA). The apparent binding constants were determined by fluorescence titration to be 0.37 x 10(6) M(-1) for 1 and 2.2 x 10(6) M(-1) for 2. The energy of the Trp-214 fluorescence of HSA is transferred to the HSA-bound fluorophores with near 100% efficiency. The covalent bonding of acrylodan (AC) to Cys-34 has little effect on the binding affinity of 2 to HSA or fluorescent behavior of HSA-bound 2. Bound 2 also has little effect on the fluorescence of AC, but 2-->AC and Trp-214-->2-->AC resonance energy transfers were observed. Competitive binding between the fluorene compounds and other ligands such as 1-anilino-8-naphthalenesulfonate, aspirin, S-(+)-ibuprofen and phenylbutazone were also studied fluorometrically. The results indicated that the primary binding site of 2 to HSA is site II in domain IIIA, whereas 1 binds to site I in domain IIA, but a different region from the phenylbutazone binding site. Because of its large molar absorptivity, strong fluorescence, sensitivity to its environment, and high binding constant to HSA, 2 can be used successfully in the study of proteins and their binding properties.