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1.
Proc Natl Acad Sci U S A ; 116(14): 6548-6553, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30886101

RESUMO

For a long time, social scientists have used correlations in social status, measured by such characteristics as schooling, income, or occupation, across family members to capture family resemblance in social status. In this study, we use millions of records from a public registry to estimate the wealth correlations among Taiwanese kinship members, from the closest parent-child pairing to the farthest kinship ties, with only 1/32 genetic relatedness. Based on this wealth correlation, we present a complete picture of economic similarity among kin members. These correlations give us a better grasp of the hitherto obscure Chinese family structure than that of mechanical genetic relatedness. We obtain statistical evidence to support the following hypotheses: Family members' wealth resemblance to male egos is stronger than to female egos, wealth correlations are larger along patrilineal lines than along matrilineal counterparts, wealthy families have larger correlations within the nuclear family members but smaller correlations outside it, and adopted children have weaker wealth resemblance with close relatives.


Assuntos
Ego , Renda , Relações Pais-Filho , Sistema de Registros , Povo Asiático , Feminino , Humanos , Masculino , Fatores Socioeconômicos , Taiwan
2.
J Phys Chem Lett ; 15(36): 9311-9318, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39235329

RESUMO

New perovskite materials of two-dimensional (2D) all-inorganic Ruddlesden-Popper (RP) perovskite Cs6Pb5I16 nanosheets were successfully obtained from the structural transformation of 2D PR-phase Cs7Pb6I19 nanosheets. The 2D RP-phase Cs6Pb5I16 perovskite nanosheets exhibited unique green emission with an emission wavelength of ∼500 nm. The crystal structure of the 2D RP-phase Cs6Pb5I16 perovskite nanosheets was determined by powder X-ray diffraction (XRD), high-resolution transmission electron microscopy, and atomic force microscopy. The time-dependent photoluminescence measurements and XRD spectra were used to observe the optical and structure transformations from 2D Cs7Pb6I19 (n = 6) to 2D Cs6Pb5I16 (n = 5) perovskites. The in situ XRD measurements confirmed that γ-phase CsPbI3 was released during the structural transformation. Moreover, temperature-dependent in situ XRD measurements were employed to examine the kinetic energy involved in the structural transformation from the n = 6 form to the n = 5 form. Specifically, an intermediate structure from n = 6 to n = 5 was also identified. Most importantly, 2D Cs6Pb5I16 (n = 5) was more structurally thermodynamically stable than 2D Cs7Pb6I19 (n = 6). This study provides an essential route for the discovery of new types of perovskite structures during structural transformation.

3.
Int J Syst Evol Microbiol ; 63(Pt 12): 4469-4476, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23859943

RESUMO

Two Gram-staining-negative, yellow-pigmented, rod-shaped, strictly aerobic, non-flagellated and non-spore-forming amylolytic marine bacterial strains, designated CC-AMZ-30M(T) and CC-AMZ-30N(T), were isolated from coastal surface seawater in Taiwan. Strain CC-AMZ-30M(T) shared pairwise 16S rRNA gene sequence similarities of 95.8, 95.0 and <94.0 % to Sphingomicrobium lutaoense CC-TBT-3(T), Sphingomicrobium astaxanthinifaciens CC-AMO-30B(T) and other sphingomonads, respectively. Strain CC-AMZ-30N(T) shared 97.0, 96.7, 95.0 and <95.1 % similarities to strain CC-AMZ-30M(T), Sphingomicrobium lutaoense CC-TBT-3(T), Sphingomicrobium astaxanthinifaciens CC-AMO-30B(T) and other sphingomonads, respectively. The common polar lipids of the two strains include a signature glycolipid (GL2), diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and sphingoglycolipid in major amounts besides moderate-to-trace amounts of an unidentified aminolipid and several unidentified glycolipids. Both strains contained C18 : 1ω7c/C18 : 1ω6c, C16 : 1ω7c/C16 : 1ω6c, C16 : 0 and C18 : 1 2-OH as major (>5 % of the total) fatty acids. Strains CC-AMZ-30M(T) and CC-AMZ-30N(T) had DNA G+C contents of 64.2 and 65.2 mol%, respectively. The major polyamine was spermidine in strain CC-AMZ-30M(T) and triamine sym-homospermidine in strain CC-AMZ-30N(T). Both strains contained ubiquinone Q-10 as the predominant respiratory quinone. Differential phylogenetic and chemotaxonomic evidence including the presence of characteristic GL2, C18 : 1 2-OH and several other phenotypic features supported the classification of strains CC-AMZ-30M(T) and CC-AMZ-30N(T) as two novel species of the genus Sphingomicrobium, for which we propose the names Sphingomicrobium marinum sp. nov. and Sphingomicrobium flavum sp. nov., respectively; corresponding type strains are Sphingomicrobium marinum CC-AMZ-30M(T) ( = JCM 18554(T) = BCRC 80466(T)) and Sphingomicrobium flavum CC-AMZ-30N(T) ( = JCM 18555(T) = BCRC 80467(T)). An emended description of the genus Sphingomicrobium is also proposed.


Assuntos
Filogenia , Água do Mar/microbiologia , Sphingomonadaceae/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Dados de Sequência Molecular , Poliaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sphingomonadaceae/genética , Sphingomonadaceae/isolamento & purificação , Taiwan , Ubiquinona/química
4.
Nanomaterials (Basel) ; 12(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35683671

RESUMO

Various types of 2D organic-inorganic perovskite solar cells have been developed and investigated due to better electron transport behavior and environmental stability. Controlling the formation of phases in the 2D perovskite films has been considered to play an important role in influencing the stability of perovskite materials and their performance in optoelectronic applications. In this work, Lewis base urea was used as an effective additive for the formation of 2D Ruddlesden-Popper (RP) perovskite (BA)2(MA)n-1PbnI3n+1 thin film with mixed phases (n = 2~4). The detailed structural morphology of the 2D perovskite thin film was investigated by in situ X-ray diffraction (XRD), grazing-incidence small-angle X-ray scattering (GISAXS) and photoluminescence mapping. The results indicated that the urea additive could facilitate the formation of 2D RP perovskite thin film with larger grain size and high crystallinity. The 2D RP perovskite thin films for solar cells exhibited a power conversion efficiency (PCE) of 7.9% under AM 1.5G illumination at 100 mW/cm2.

5.
Mater Horiz ; 9(9): 2433-2442, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35848594

RESUMO

Two-dimensional (2D) all-inorganic Ruddlesden-Popper (RP) perovskite Cs7Pb6I19 nanosheets (NSs) were successfully developed for the first time by employing a structural recrystallization process with additional passivation of small organic sulfide molecules. The structure of Cs7Pb6I19 NSs is confirmed by powder X-ray diffraction measurements, atomically-resolved STEM measurements and atomic force microscopy (AFM) studies. Cs7Pb6I19 NSs with a specific n value of 6 exhibits unique absorption and emission spectra with intense excitons at 560 nm due to quantum confinement effects in 2D perovskite slabs. The formation mechanisms of 2D Cs7Pb6I19 NSs and 3D γ-CsPbI3 phases were investigated by in situ photoluminescence (PL) spectroscopy and the activation energies of their formation reactions were calculated to be 151 kJ mol-1 and 95.3 kJ mol-1, respectively. The phase stability of 2D Cs7Pb6I19 NSs can be maintained at temperatures below 14 °C for more than 4 weeks. The overall results indicate that 2D Cs7Pb6I19 NSs demonstrate unique optical properties and structural stability compared with other 3D perovskite materials. We have opened a new path to the future discovery of 2D perovskite structures with metastable phases by using this recrystallization method and the assistance of sulfur-derived organic molecules.

6.
J Phys Chem Lett ; 12(36): 8763-8769, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34491065

RESUMO

Metal halide perovskites have attracted great attention for their superior light energy conversion applications. Herein, we demonstrated a facile synthesis of zero-dimensional Sn2+ perovskite Cs4-xMxSnBr6(M = K+ and Rb+) material through the cation transformation reaction at room temperature. Cs4SnBr6 NCs was mixed with pure metal bromide salts (KBr and RbBr) via the mechanochemical process to successfully synthesize Cs4-xMxSnBr6 perovskite where transformation of Cs to mixed Cs/Rb and mixed Cs/K was achieved. By substituting different cations, the bright fluorescence of the Cs4-xMxSnBr6 was tuned from dim green to greenish-cyan while achieving the photoluminescence (PL) quantum yield of ∼39%. The crystal structure of Sn based perovskite with the substitution of K+ or Rb+ cations was determined by X-ray diffraction (XRD). Moreover, the Cs4-xMxSnBr6 demonstrated superior air stability and exhibited a better photocatalytic activity for CO2 reduction reaction (CO2RR) with high selectivity of CH4 gas with a higher yield rate compared to the pristine Cs4SnBr6 NCs.

7.
ACS Appl Mater Interfaces ; 12(23): 25853-25860, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32406673

RESUMO

Intensive energy demand urges state-of-the-art rechargeable batteries. Rechargeable aluminum-ion batteries (AIBs) are promising candidates with suitable cathode materials. Owing to high abundance of carbon, hydrogen, and oxygen and rich chemistry of organics (structural diversity and flexibility), small organic molecules are good choices as the electrode materials for AIB. Herein, a series of small-molecule quinone derivatives (SMQD) as cathode materials for AIB were investigated. Nonetheless, dissolution of small organic molecules into liquid electrolytes remains a fundamental challenge. To nullify the dissolution problem effectively, 1,4-benzoquinone was integrated with four bulky phthalimide groups to form 2,3,5,6-tetraphthalimido-1,4-benzoquinone (TPB) as the cathode materials and assembled to be the AI/TPB cell. As a result, the Al/TPB cell delivered capacity as high as 175 mA h/g over 250 cycles in the urea electrolyte system. Theoretical studies have also been carried out to reveal and understand the storage mechanism of the TPB electrode.

8.
Nanoscale Res Lett ; 13(1): 247, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30136147

RESUMO

In hybrid organic-inorganic and all-inorganic metal halide perovskite nanomaterials, two-dimensional (2D) Ruddlesden-Popper (RP) perovskites have become one of the most interesting materials because of tunable bandgaps varied with the layer thickness, effective modulation of the electron-hole confinement, and high stability. Here, we report a one-pot synthesis of 2D RP perovskite (BA)2(MA)n - 1PbnX3n + 1 (BA = 1-butylammonium, MA = methylammonium, X = Br or I) quantum dots (QDs) with an average size of 10 nm at room temperature. The (BA)2(MA)n - 1PbnBr3n + 1 (Br series) QDs and (BA)2(MA)n - 1PbnI3n + 1 (I series) QDs exhibited tunable emitting spectrum in the range of 410-523 nm and 527-761 nm, respectively, with full width at half maximum (FWHM) of 12-75 nm. The emission color was tuned by the ratio of MA and halide. The photoluminescence quantum yield of 2D perovskite QDs reached 48.6% with more thermodynamic stability in comparison with 3D MAPbX3 QDs. Overall results indicated that developing a solution synthesis for 2D RP perovskite QDs with great optical properties paves the way toward future optoelectronic devices and perovskite quantum dot photovoltaics.

9.
World J Gastroenterol ; 24(10): 1152-1166, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29563759

RESUMO

AIM: To investigate the clinicopathological significance of progesterone receptor membrane component 1 (PGRMC1) and PGRMC2 in hepatocellular carcinoma (HCC). METHODS: We performed immunohistochemical staining to evaluate the estrogen receptor (ER), progesterone receptor (PR), PGRMC1, and PGRMC2 in a clinical cohort consisting of 89 paired HCC and non-tumor liver samples. We also analyzed HCC data (n = 373) from The Cancer Genome Atlas (TCGA). We correlated the expression status of PGRMC1 and PGRMC2 with clinicopathological indicators and the clinical outcomes of the HCC patients. We knocked down or overexpressed PGRMC1 in HCC cell lines to evaluate its biological significance in HCC cell proliferation, differentiation, migration, and invasion. RESULTS: We found that few HCC cases expressed ER (5.6%) and PR (4.5%). In contrast, most HCC cases expressed PGRMC1 (89.9%) and PGRMC2 (100%). PGRMC1 and PGRMC2 exhibited significantly lower expression in tumor tissue than in non-tumor tissue (P < 0.001). Lower PGRMC1 expression in HCC was significantly associated with higher serum alpha-fetoprotein expression (P = 0.004), poorer tumor differentiation (P = 0.045) and liver capsule penetration (P = 0.038). Low PGRMC1 expression was an independent predictor for worse disease-free survival (P = 0.002, HR = 2.384, CI: 1.377-4.128) in our cases, as well as in the TCGA cohort (P < 0.001, HR = 2.857, CI: 1.781-4.584). The expression of PGRMC2 did not relate to patient outcome. PGRMC1 knockdown promoted a poorly differentiated phenotype and proliferation of HCC cells in vitro, while PGRMC1 overexpression caused the opposite effects. CONCLUSION: PGRMC1 is a non-classical hormonal receptor that negatively regulates hepatocarcinogenesis. PGRMC1 down-regulation is associated with progression of HCC and is a poor prognostic indicator.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Proteínas de Membrana/metabolismo , Receptores de Progesterona/metabolismo , Carcinogênese/patologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/cirurgia , Diferenciação Celular , Movimento Celular , Proliferação de Células , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Fígado/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética
10.
Nanoscale ; 7(34): 14532-7, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26260838

RESUMO

To replace high-temperature sintered scaffold materials in conventional CH3NH3PbI3-based solar cells, this study demonstrates a new device structure of a bulk intermixing (BI)-type CH3NH3PbI3/TiO2 nanorod (NR) hybrid solar cell, where dispersed TiO2 NRs from chemical synthesis are intermixed with the perovskite absorbing layer to form a BI-type perovskite/TiO2 NR hybrid for device fabrication. Through interface engineering between the TiO2 NR surface and the photoactive perovskite material of CH3NH3PbI3 by ligand exchange treatment, a remarkable power conversion efficiency (PCE) of over 12% was achieved based on the simple BI-type CH3NH3PbI3/TiO2 NR hybrid device structure. The proposed hybrids not only provide great flexibility for deposition on various substrates through spin coating at low temperatures but also enable layer-by-layer deposition for the future development of perovskite-based multi-junction solar cells.

11.
Kaohsiung J Med Sci ; 30(3): 116-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24581211

RESUMO

Eugenosedin-A (Eu-A) effects on vascular endothelial dysfunction and oxidative stress in a hyperlipidemic rat model were investigated. Rats were randomly divided into four groups: two control groups and two treatment groups. The control rats received a regular diet or high fat diet (HFD); the treatment rats fed received an HFD with 5 mg/kg Eu-A or atorvastatin for 10 weeks. No changes in serotonin levels were observed in the four groups; norepinephrine levels were enhanced in the HFD group which was attenuated by Eu-A and atorvastatin. In the HFD group, the vascular reactivity was increased by vasoconstrictors (5-nonyloxytryptamine, 5-HT, and phenylephrine) and decreased by an endothelium-dependent vasorelaxant, carbachol. Protein levels of α1-adrenergic receptors (not 5-HT1B/2A), reactive oxygen species (ROS) p47(phox), p67(phox), and gp91(phox), and oxidative damage markers 3-nitrotyrosine (3-NT) and 4-hydroxy-2-nonenal (4-HNE) were increased, but endothelial nitric oxide synthase (eNOS), P-eNOS and vasodilator-stimulated phosphoprotein phosphorylation (P-VASP) were decreased. Catalase and superoxide dismutase (SOD-1 and SOD-2) proteins were increased, but glutathione peroxidase (GPx) was decreased in the aorta. Eu-A and atorvastatin reduced vasoconstrictor-induced aortic contractions that might be related to 5-HT1B/2A and α1-adrenergic receptors inhibitory activities. Eu-A and atorvastatin improved eNOS/P-eNOS, P-VASP, GPx, and malondialdehyde (MDA) levels, and decreased ROS and oxidative damage markers. Taken together, we suggest that Eu-A can ameliorate hyperlipidemia-induced vascular endothelial dysfunction and oxidative dysregulation.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Hiperlipidemias/complicações , NADPH Oxidases/metabolismo , Piperazinas/farmacologia , Receptores Adrenérgicos/metabolismo , Serotonina/metabolismo , Animais , Aorta Torácica , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Moléculas de Adesão Celular/metabolismo , Masculino , Malondialdeído/metabolismo , Proteínas dos Microfilamentos/metabolismo , Norepinefrina/sangue , Estresse Oxidativo/efeitos dos fármacos , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Serotonina/sangue , Superóxido Dismutase/metabolismo
12.
J Pharm Pharmacol ; 65(2): 300-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23278698

RESUMO

OBJECTIVES: Previous studies have shown eugenosedin-A, a 5-HT(1B/2A) and α(1)/α(2)/ß(1)-adrenergic blocker, is able to decrease cholesterol levels, hyperglycaemia and inflammation in hyperlipidaemic mice induced by high-fat diet (HFD). The aim of this study is to examine the effects of eugenosedin-A on the inhibition of adhesion molecules of platelets, the aorta and acyl-coenzymeA:cholesterol acyltransferase-1 (ACAT-1) of macrophages in a hyperlipidaemic rat model. METHODS: Six-week-old Sprague-Dawley rats were randomly divided into two control and treatment groups. The control rats received either a regular diet or HFD and the treatment groups were fed HFD with either 5 mg/kg eugenosedin-A or atorvastatin for a 10-week period. KEY FINDINGS: Compared with the two control groups, the HFD group had lower levels of high-density lipoprotein, higher concentrations of triglycerides, total cholesterol, low-density lipoprotein and insulin. The expression of adhesion molecules in platelets, aorta and monocyte-macrophage were enhanced by HFD. HFD also increased upstream proteins and their phosphorylated form in the aorta. In treatment groups, eugenosedin-A and atorvastatin improved HFD-induced hyperlipidaemia and levels of insulin. Eugenosedin-A reduced the upregulation of P-selectin, ICAM-1, ICAM-2, ICAM-3, VCAM, PECAM in platelets and inhibited E-selectin, ICAM-1, ICAM-2, ICAM-3, VCAM and PECAM protein levels in the aorta. Eugenosedin-A reduced the ACAT-1 protein expression of monocyte-macrophages. The expression of PKCα, MAPKs, IKKα and p65 and their phosphorylated form were reduced in treatment groups. CONCLUSIONS: Taken together, hyperlipidaemia enhances the expression of adhesion molecules and ACAT-1 protein, and eugenosedin-A ameliorates those increases. Through inhibition of MAPK- and p-65-mediated NF-κB pathway, eugenosedin-A decreases the quantity of adhesion molecules.


Assuntos
Moléculas de Adesão Celular/metabolismo , Dieta Hiperlipídica/efeitos adversos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , Piperazinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/antagonistas & inibidores , Acetil-CoA C-Acetiltransferase/metabolismo , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Selectina E/metabolismo , Hiperlipidemias/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Transcrição RelA/metabolismo
13.
J Clin Virol ; 45(4): 285-91, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19473877

RESUMO

BACKGROUND: Epidemics of acute hemorrhagic conjunctivitis (AHC) caused by a coxsackievirus A24 variant (CA24v) appeared in Taiwan in 2000-2002 and again in 2006-2007. OBJECTIVE: To analyze the molecular epidemiology of CA24v in recent outbreaks in Taiwan. STUDY DESIGN: A 510bp fragment of 3C(pro) region was analyzed in 30 CA24v isolates during 2000-2007. Phylogenetic tree was constructed along with 130 CA24v isolates available from the GenBank. Moreover, the 235bp of 3'VP1 region was similarly analyzed in 15 randomly selected strains isolated during 1985-2007. Phylogenetic dendrogram was constructed for the 3'VP1 region in 105 CA24v strains worldwide. Genetic distances were calculated using Kimura 2-parameter model, and phylogenetic trees were constructed by neighbor-joining method. RESULTS: The 3C(pro) dendrogram depicted genotype IV (GIV), a new genotype that can be further divided into three clusters (C1-C3). The 2000-2002 outbreaks were caused by genotype IV-cluster 1 (GIV-C1) and GIV-C2. Strains isolated in the 2006-2007 outbreak belong to GIV-C3, also in the same cluster as Singapore strains from 2005. Analysis on 3'VP1 revealed only GI, GIII and GIV in line with the classification in 3C(pro) dendrogram. All genotype IV strains were also divided into three clusters, though the GIV-C 2' were isolated from broader geographic areas and over a longer period of time. CONCLUSIONS: Analysis of the 3C(pro) region is more insightful than the 3'VP1 region in the molecular epidemiology of CA24v. The 3C(pro) dendrogram accurately and chronologically identified all stains involved in the worldwide outbreaks.


Assuntos
Conjuntivite Viral/epidemiologia , Conjuntivite Viral/virologia , Infecções por Coxsackievirus/epidemiologia , Infecções por Coxsackievirus/virologia , Surtos de Doenças , Enterovirus Humano C/classificação , Enterovirus Humano C/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise por Conglomerados , Enterovirus Humano C/isolamento & purificação , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Taiwan/epidemiologia , Proteínas Virais/genética , Adulto Jovem
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