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1.
Heliyon ; 10(8): e29400, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644856

RESUMO

Companies with excess capital can opt to: pay dividends to shareholders, buy back treasury shares for short-term shareholder benefits, or pursue M&A investments for long-term shareholder returns. Using difference in differences approach of event research methods combined with unique manually collected data sets, this paper investigates the market bias for three events: M&A, share repurchase, and dividend payment. The results show that information was leaked to the outside 1 day before it was officially announced at all events. When observing the company's performance 3 years after the event announcement, we also find that the market reaction is biased in M&A and stock dividend payment events, but accurate in the cash dividend payment and share repurchases. In addition, the market has the strongest and longest reaction to the news of the company buying back shares; has the weakest reaction to the stock dividend payment; has the shortest reaction to cash dividend payment; has a negative reaction to the acquisition company's stock, and has a positive reaction to the target company's stock. Our research has provided empirical evidence on the market response to published information, and supports CEOs make the most accurate choices when the company has an excess cash flow.

2.
Chem Biodivers ; 21(5): e202400518, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38501574

RESUMO

In this study, two undescribed compounds (1 and 2), together with eight known compounds (3-10) were isolated from the aerial parts of Piper samentosum by various chromatography methods. Their chemical structures were determined to be 7'''-oxolyciumamide N (1), vitexin 2''-O-ß-D-(6'''-feruloyl)-glucopyranoside (2), 1,2-dihydro-6,8-dimethoxy-7-hydroxy-1-(3,4-dihydroxyphenyl)-N1,N2-bis-[2-(-hydroxyphenyl)ethyl]-2,3-napthalene dicarboamide (3), vitexin 6''-O-ß-D-glucopyranoside (4), vitexin 2''-O-α-L-rhamnopyranoside (5), methyl 2-hydroxybenzoate-2-O-ß-D-apiofuranosyl-(1→2)-O-ß-D-glucopyranoside (6), ficuside G (7), methyl 2-O-ß-D-glucopyranosylbenzoate (8), methyl 2,5-dihydroxybenzoate-5-O-ß-D-glucopyranoside (9), and 3,7-dimethyloct-1-ene-3,6,7-triol 6-O-ß-D-glucopyranoside (10) by spectroscopic data analysis including HR-ESI-MS, 1D-, and 2D-NMR spectra. Compounds 1-5 inhibited nitric oxide production in LPS-stimulated RAW264.7 macrophages with the IC50 values of 27.62, 74.03, 38.54, 70.39, and 44.95 µM, respectively. The NMR data of 9 were firstly reported herein.


Assuntos
Flavonas , Glucosídeos , Lipopolissacarídeos , Óxido Nítrico , Piper , Componentes Aéreos da Planta , Células RAW 264.7 , Camundongos , Animais , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Componentes Aéreos da Planta/química , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Glucosídeos/química , Piper/química , Flavonas/isolamento & purificação , Flavonas/farmacologia , Flavonas/química , Amidas/química , Amidas/farmacologia , Amidas/isolamento & purificação , Estrutura Molecular
3.
Emerg Infect Dis ; 29(10): 2130-2134, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37735771

RESUMO

We report on an outbreak of nongroupable Neisseria meningitidis-associated urethritis, primarily among men who have sex with men in southern Vietnam. Nearly 50% of N. meningitidis isolates were resistant to ciprofloxacin. This emerging pathogen should be considered in the differential diagnosis and management of urethritis.


Assuntos
Neisseria meningitidis , Minorias Sexuais e de Gênero , Uretrite , Masculino , Humanos , Uretrite/diagnóstico , Uretrite/epidemiologia , Vietnã/epidemiologia , Homossexualidade Masculina , Surtos de Doenças , Neisseria meningitidis/genética
4.
Gen Dent ; 71(5): 38-44, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37595082

RESUMO

Demand for direct esthetic restorations is high, but shade matching can be challenging. Some manufacturers claim that a single product is able to match all colors of the human dentition, eliminating shade matching challenges. This in vivo study, which followed the International Commission on Illumination's (CIE) CIEDE2000 color difference standard (ΔE00), aimed to quantify the shade matching and blending capabilities of a single-shade composite (Omnichroma PLT) used as a direct veneer. A color difference of ΔE00 ≤ 1.8 was set as the acceptability threshold. Ten participants with an unrestored and noncarious maxillary left central incisor were enrolled in the study. Direct spectrophotometric measurements (CIE L*a*b*) were made on the tooth and then on composite cured on the tooth. Consistency in measurements and composite resin placement were attained through the use of a specially designed jig. A digital photograph was then taken with the composite in place, and colorimetric software was used to obtain the L*a*b* values at the most incisal and cervical edges of the restoration. These values were compared to those of the natural tooth structure immediately adjacent to the composite resin. The ΔE00 scores were calculated to determine the composite's ability to match the tooth shade beneath it (ΔEm) and to blend with the incisal (ΔEi) and cervical (ΔEc) tooth shades. Mean scores for ΔEm, ΔEi, and ΔEc were calculated, and an independent t test (α = 0.05) was used to compare means for ΔEi and ΔEc. The mean (SD) ΔE00 values were 6.16 (2.38), 3.90 (2.47), and 6.84 (1.80) for ΔEm, ΔEi, and ΔEc, respectively. A statistically significant difference (P = 0.008) was observed between ΔEi and ΔEc. As a direct veneer, the tested composite did not meet the acceptability threshold for any ΔE00 measurement; however, it was better at matching the incisal third of the tooth than it was the other thirds. More in vivo studies are needed to verify and expand on these results.


Assuntos
Colorimetria , Resinas Compostas , Humanos , Cor , Colorimetria/métodos , Espectrofotometria , Resinas Compostas/uso terapêutico , Resinas Compostas/química , Teste de Materiais
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