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1.
Nature ; 603(7901): 434-438, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35296844

RESUMEN

Oxidation can deteriorate the properties of copper that are critical for its use, particularly in the semiconductor industry and electro-optics applications1-7. This has prompted numerous studies exploring copper oxidation and possible passivation strategies8. In situ observations have, for example, shown that oxidation involves stepped surfaces: Cu2O growth occurs on flat surfaces as a result of Cu adatoms detaching from steps and diffusing across terraces9-11. But even though this mechanism explains why single-crystalline copper is more resistant to oxidation than polycrystalline copper, the fact that flat copper surfaces can be free of oxidation has not been explored further. Here we report the fabrication of copper thin films that are semi-permanently oxidation resistant because they consist of flat surfaces with only occasional mono-atomic steps. First-principles calculations confirm that mono-atomic step edges are as impervious to oxygen as flat surfaces and that surface adsorption of O atoms is suppressed once an oxygen face-centred cubic (fcc) surface site coverage of 50% has been reached. These combined effects explain the exceptional oxidation resistance of ultraflat Cu surfaces.

2.
J Proteome Res ; 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231884

RESUMEN

ARID3C is a protein located on human chromosome 9 and expressed at low levels in various organs, yet its biological function has not been elucidated. In this study, we investigated both the cellular localization and function of ARID3C. Employing a combination of LC-MS/MS and deep learning techniques, we identified NPM1 as a binding partner for ARID3C's nuclear shuttling. ARID3C was found to predominantly localize with the nucleus, where it functioned as a transcription factor for genes STAT3, STAT1, and JUNB, thereby facilitating monocyte-to-macrophage differentiation. The precise binding sites between ARID3C and NPM1 were predicted by AlphaFold2. Mutating this binding site prevented ARID3C from interacting with NPM1, resulting in its retention in the cytoplasm instead of translocation to the nucleus. Consequently, ARID3C lost its ability to bind to the promoters of target genes, leading to a loss of monocyte-to-macrophage differentiation. Collectively, our findings indicate that ARID3C forms a complex with NPM1 to translocate to the nucleus, acting as a transcription factor that promotes the expression of the genes involved in monocyte-to-macrophage differentiation.

3.
Molecules ; 27(14)2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35889464

RESUMEN

The annual herb Euphorbia maculata L. produces anti-inflammatory and biologically active substances such as triterpenoids, tannins, and polyphenols, and it is used in traditional Chinese medicine. Of these bioactive compounds, terpenoids, also called isoprenoids, are major secondary metabolites in E. maculata. Full-length cDNA sequencing was carried out to characterize the transcripts of terpenoid biosynthesis reference genes and determine the copy numbers of their isoforms using PacBio SMRT sequencing technology. The Illumina short-read sequencing platform was also employed to identify differentially expressed genes (DEGs) in the secondary metabolite pathways from leaves, roots, and stems. PacBio generated 62 million polymerase reads, resulting in 81,433 high-quality reads. From these high-quality reads, we reconstructed a genome of 20,722 genes, in which 20,246 genes (97.8%) did not have paralogs. About 33% of the identified genes had two or more isoforms. DEG analysis revealed that the expression level differed among gene paralogs in the leaf, stem, and root. Whole sets of paralogs and isoforms were identified in the mevalonic acid (MVA), methylerythritol phosphate (MEP), and terpenoid biosynthesis pathways in the E. maculata L. The nucleotide information will be useful for identifying orthologous genes in other terpenoid-producing medicinal plants.


Asunto(s)
Euphorbia , ADN Complementario/genética , Euphorbia/genética , Euphorbia/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Secuenciación de Nucleótidos de Alto Rendimiento , Terpenos/metabolismo , Transcriptoma/genética
4.
Nucleic Acids Res ; 47(6): 2840-2855, 2019 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-30649429

RESUMEN

RNF20/40 E3 ubiquitin ligase-mediated histone H2B monoubiquitylation plays important roles in many cellular processes, including transcriptional regulation. However, the multiple defects observed in RNF20-depleted cells suggest additional ubiquitylation targets of RNF20/40 beyond histone H2B. Here, using biochemically defined assays employing purified factors and cell-based analyses, we demonstrate that RNF20/40, in conjunction with its cognate E2 ubiquitin-conjugating enzyme RAD6, monoubiquitylates lysine 381 of eEF1BδL, a heat shock transcription factor. Notably, monoubiquitylation of eEF1BδL increases eEF1BδL accumulation and potentiates recruitment of p-TEFb to the promoter regions of heat shock-responsive genes, leading to enhanced transcription of these genes. We further demonstrate that cooperative physical interactions among eEF1BδL, RNF20/40, and HSF1 synergistically promote expression of heat shock-responsive genes. In addition to identifying eEF1BδL as a novel ubiquitylation target of RNF20/40 and elucidating its function, we provide a molecular mechanism for the cooperative function of distinct transcription factors in heat shock-responsive gene transcription.


Asunto(s)
Respuesta al Choque Térmico , Factor 1 de Elongación Peptídica/metabolismo , Transcripción Genética , Ubiquitina-Proteína Ligasas/fisiología , Animales , Regulación de la Expresión Génica , Células HEK293 , Respuesta al Choque Térmico/genética , Humanos , Unión Proteica , Multimerización de Proteína , Células Sf9 , Spodoptera , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/genética
5.
Nano Lett ; 20(11): 8353-8359, 2020 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-33111527

RESUMEN

Visualizing the oxygen vacancy distributions is highly desirable for understanding the atomistic oxygen diffusion mechanisms in perovskites. In particular, the direct observation of the one-dimensional oxygen vacancy channels has not yet been achieved in perovskites with dual ion (i.e., cation and anion) ordering. Here, we perform atomic-resolution imaging of the one-dimensional oxygen vacancy channels and their structural dynamics in a NdBaCo2O5.5 double perovskite oxide. An in situ heating transmission electron microscopy investigation reveals the disordering of oxygen vacancy channels by local rearrangement of oxygen vacancies at the specific temperature. A density functional theory calculation suggests that the possible pathway of oxygen vacancy migration is a multistep route via Co-O and Nd-Ov (oxygen vacancy) sites. These findings could provide robust guidance for understanding the static and dynamic behaviors of oxygen vacancies in perovskite oxides.

6.
BMC Complement Altern Med ; 19(1): 134, 2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31215445

RESUMEN

BACKGROUND: Calotropis gigantea (CG) is a tall and waxy flower that is used as a traditional remedy for fever, indigestion, rheumatism, leprosy, and leukoderma. However, the precise mechanisms of its anticancer effects have not yet been examined in human non-small cell lung cancer (NSCLC) cells. In this study, we investigated whether CG extract exerted an apoptotic effect in A549 and NCI-H1299 NSCLC cells. METHODS: The ethanol extract of CG was prepared, and its apoptotic effects on A549 and NCI-H1299 NSCLC cells were assessed by using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxy methoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay, annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining, cell cycle analysis, real-time polymerase chain reaction (RT-PCR), western blotting, JC-1 staining, and ROS detection assay. RESULTS: The CG extract induced apoptosis through the stimulation of intrinsic and extrinsic signaling pathways in A549 and NCI-H1299 lung cancer cells. Cell cycle arrest was induced by the CG extract in both cell lines. Reactive oxygen species (ROS), which can induce cell death, were also generated in the CG-treated A549 and NCI-H1299 cells. CONCLUSIONS: These data confirmed that CG caused apoptosis through the activation of extrinsic and intrinsic pathways, cell cycle arrest, and ROS generation in A549 and NCI-H1299 lung cancer cells. Thus, CG can be suggested as a potential agent for lung cancer therapy.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Calotropis/química , Medicamentos Herbarios Chinos/farmacología , Neoplasias Pulmonares/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatología
7.
Int J Mol Sci ; 19(10)2018 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-30336636

RESUMEN

As lung cancer shows the highest mortality in cancer-related death, serum biomarkers are demanded for lung cancer diagnosis and its treatment. To discover lung cancer protein biomarkers, secreted proteins from primary cultured lung cancer and adjacent normal tissues from patients were subjected to LC/MS⁻MS proteomic analysis. Quiescin sulfhydryl oxidase (QSOX1) was selected as a biomarker candidate from the enriched proteins in the secretion of lung cancer cells. QSOX1 levels were higher in 82% (51 of 62 tissues) of lung cancer tissues compared to adjacent normal tissues. Importantly, QSOX1 serum levels were significantly higher in cancer patients (p < 0.05, Area Under curve (AUC) = 0.89) when measured by multiple reaction monitoring (MRM). Higher levels of QSOX1 were also uniquely detected in lung cancer tissues, among several other solid cancers, by immunohistochemistry. QSOX1-knock-downed Lewis lung cancer (LLC) cells were less viable from oxidative stress and reduced migration and invasion. In addition, LLC mouse models with QSOX1 knock-down also proved that QSOX1 functions in promoting cancer metastasis. In conclusion, QSOX1 might be a lung cancer tissue-derived biomarker and be involved in the promotion of lung cancers, and thus can be a therapeutic target for lung cancers.


Asunto(s)
Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/metabolismo , Secuencia de Aminoácidos , Animales , Biomarcadores de Tumor/metabolismo , Línea Celular Tumoral , Progresión de la Enfermedad , Técnicas de Silenciamiento del Gen , Ontología de Genes , Humanos , Neoplasias Pulmonares/sangre , Masculino , Ratones Endogámicos C57BL , Metástasis de la Neoplasia , Oxidorreductasas actuantes sobre Donantes de Grupos Sulfuro/sangre , Péptidos/química , Proteoma/metabolismo , Reproducibilidad de los Resultados
8.
Molecules ; 22(6)2017 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-28608837

RESUMEN

The traditional herbal medicine, Hochu-ekki-to, has been shown to have preventive effects on viral infection and stress. This study aimed to evaluate the clinical effects of Hochu-ekki-to on two stress-related rat models of polycystic ovarian syndrome. Female Sprague-Dawley rats were divided into control and treatment groups, the latter of which were subjected to stress induced by exposure to adrenocorticotropic hormone (ACTH) or cold temperatures. After these stress inductions, rats were orally treated with dissolved Hochu-ekki-to once per day for 7 days. Rats subjected to the two different stressors exhibited upregulation of steroid hormone receptors (in ovaries) and reproductive hormones (in blood), and consequent stimulation of abnormal follicle development accompanied by elevation of Hsp 90 expression (in ovaries). Treatment with Hochu-ekki-to for 7 days after stress induction increased immune functions, reduced the stress-induced activation of Hsp 90, and normalized the levels of the tested steroid hormone receptors and reproductive hormones. Our findings suggest that stress stimulations may promote the activation of Hsp 90 via the dysregulation of steroid hormone receptors and reproductive hormones, but that post-stress treatment with Hochu-ekki-to improves reproductive and immune functions in the ovaries of stressed rats.


Asunto(s)
Medicamentos Herbarios Chinos/administración & dosificación , Proteínas HSP90 de Choque Térmico/genética , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Reproducción/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Hormona Adrenocorticotrópica/toxicidad , Animales , Frío , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunomodulación/efectos de los fármacos , Ovario/efectos de los fármacos , Ovario/fisiopatología , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/patología , Ratas , Estrés Fisiológico/genética
9.
J Proteome Res ; 15(12): 4146-4164, 2016 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-27760464

RESUMEN

Glycoprotein conformations are complex and heterogeneous. Currently, site-specific characterization of glycopeptides is a challenge. We sought to establish an efficient method of N-glycoprotein characterization using mass spectrometry (MS). Using alpha-1-acid glycoprotein (AGP) as a model N-glycoprotein, we identified its tryptic N-glycopeptides and examined the data reproducibility in seven laboratories running different LC-MS/MS platforms. We used three test samples and one blind sample to evaluate instrument performance with entire sample preparation workflow. 165 site-specific N-glycopeptides representative of all N-glycosylation sites were identified from AGP 1 and AGP 2 isoforms. The glycopeptide fragmentations by collision-induced dissociation or higher-energy collisional dissociation (HCD) varied based on the MS analyzer. Orbitrap Elite identified the greatest number of AGP N-glycopeptides, followed by Triple TOF and Q-Exactive Plus. Reproducible generation of oxonium ions, glycan-cleaved glycopeptide fragment ions, and peptide backbone fragment ions was essential for successful identification. Laboratory proficiency affected the number of identified N-glycopeptides. The relative quantities of the 10 major N-glycopeptide isoforms of AGP detected in four laboratories were compared to assess reproducibility. Quantitative analysis showed that the coefficient of variation was <25% for all test samples. Our analytical protocol yielded identification and quantification of site-specific N-glycopeptide isoforms of AGP from control and disease plasma sample.


Asunto(s)
Glicopéptidos/química , Orosomucoide/química , Isoformas de Proteínas/análisis , Sitios de Unión , Recolección de Muestras de Sangre , Cromatografía Liquida , Glicosilación , Humanos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
10.
Biochim Biophys Acta ; 1854(6): 668-76, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25463045

RESUMEN

The homodimeric glycoprotein, stanniocalcin 2 (STC2) is previously known to be involved in the regulation of calcium and phosphate transport in the kidney and also reported to play multiple roles in several cancers. However, its function and clinical significance in lung cancer have never been reported and still remain uncertain. Here, we investigated the possibility of STC2 as a lung cancer biomarker and identified its potential role in lung cancer cell growth, metastasis and progression. Proteomic analysis of secretome of primary cultured lung cancer cells revealed higher expression of STC2 in cancers compared to that of adjacent normal cells. RT-PCR and Western blot analyses showed higher mRNA and protein expressions of STC2 in lung cancer tissues compared to the adjacent normal tissues. Knockdown of STC2 in H460 lung cancer cells slowed down cell growth progression and colony formation. Further analysis revealed suppression of migration, invasion and delayed G0/G1 cell cycle progression in the STC2 knockdown cells. STC2 knockdown also attenuated the H202-induced oxidative stress on H460 cell viability with a subsequent increase in intracellular ROS levels, which suggest a protective role of STC2 in redox regulatory system of lung cancer. These findings suggest that STC2 can be a potential lung cancer biomarker and plays a positive role in lung cancer metastasis and progression. This article is part of a Special Issue entitled: Medical Proteomics.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Movimiento Celular , Fase G1 , Glicoproteínas/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias Pulmonares/metabolismo , Estrés Oxidativo , Fase de Descanso del Ciclo Celular , Adulto , Anciano , Línea Celular Tumoral , Femenino , Humanos , Peróxido de Hidrógeno/farmacología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Oxidantes/farmacología , Proteómica
11.
J Proteome Res ; 14(12): 5007-16, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26584007

RESUMEN

This is a report of a human proteome project (HPP) related to chromosome 9 (Chr 9). To reveal missing proteins and undiscovered features in proteogenomes, both LC-MS/MS analysis and next-generation RNA sequencing (RNA-seq)-based identification and characterization were conducted on five pairs of lung adenocarcinoma tumors and adjacent nontumor tissues. Before our previous Chromosome-Centric Human Proteome Project (C-HPP) special issue, there were 170 remaining missing proteins on Chr 9 (neXtProt 2013.09.26 rel.); 133 remain at present (neXtProt 2015.04.28 rel.). In the proteomics study, we found two missing protein candidates that require follow-up work and one unrevealed protein across all chromosomes. RNA-seq analysis detected RNA expression for four nonsynonymous (NS) single nucleotide polymorphisms (SNPs) (in CDH17, HIST1H1T, SAPCD2, and ZNF695) and three synonymous SNPs (in CDH17, CST1, and HNF1A) in all five tumor tissues but not in any of the adjacent normal tissues. By constructing a cancer patient sample-specific protein database based on individual RNA-seq data and by searching the proteomics data from the same sample, we identified four missense mutations in four genes (LTF, HDLBP, TF, and HBD). Two of these mutations were found in tumor samples but not in paired normal tissues. In summary, our proteogenomic study of human primary lung tumor tissues detected additional and revealed novel missense mutations and synonymous SNP signatures, some of which are specific to lung cancers. Data from mass spectrometry have been deposited in the ProteomeXchange with the identifier PXD002523.


Asunto(s)
Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Cromosomas Humanos Par 9 , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Mutación Missense , Polimorfismo de Nucleótido Simple , Adenocarcinoma del Pulmón , Adulto , Anciano , Cadherinas/genética , Cadherinas/metabolismo , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Péptidos/análisis , Péptidos/genética , Proteoma/genética , Seudogenes , ARN Largo no Codificante , Análisis de Secuencia de ARN , Espectrometría de Masas en Tándem
12.
J Biol Chem ; 289(45): 31330-40, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25237190

RESUMEN

Angiopoietin-2 (Ang-2) not only regulates angiogenesis by binding to its well known receptor Tie2 on endothelial cells but also controls sprouting of Tie2-negative angiogenic endothelial cells and invasion of Tie2-negative non-endothelial cells by binding to integrins. However, the molecular mechanism of the Ang-2/integrin association has been unclear. In this study, we found that the Gln-362 residue of Ang-2 was essential for binding to α5ß1 integrin. A Q362E Ang-2 mutant, which still bound to Tie2, failed to associate with α5ß1 integrin and was unable to activate the integrin downstream signaling of focal adhesion kinase. In addition, unlike wild-type Ang-2, the Q362E Ang-2 mutant was defective in mediating invasion of Tie2-negative glioma or Tie2-positive endothelial cells. Furthermore, the tailpiece domain of the α5 subunit in α5ß1 integrin was critical for binding to Ang-2. Taken together, these results provide a novel insight into the mechanism of integrin regulation by Ang-2, which contributes to tumor invasion and endothelial cell migration in a Tie2-independent manner.


Asunto(s)
Angiopoyetina 2/metabolismo , Células Endoteliales/citología , Glutamina/metabolismo , Integrina alfa5beta1/metabolismo , Neoplasias/metabolismo , Receptor TIE-2/metabolismo , Animales , Células CHO , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular , Cricetinae , Cricetulus , Regulación de la Expresión Génica , Humanos , Integrinas/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias/patología , Neovascularización Patológica , Plásmidos/metabolismo , Estructura Terciaria de Proteína
13.
J Proteome Res ; 13(1): 137-46, 2014 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-24274035

RESUMEN

The Chromosome-centric Human Proteome Project (C-HPP) was recently initiated as an international collaborative effort. Our team adopted chromosome 9 (Chr 9) and performed a bioinformatics and proteogenomic analysis to catalog Chr 9-encoded proteins from normal tissues, lung cancer cell lines, and lung cancer tissues. Approximately 74.7% of the Chr 9 genes of the human genome were identified, which included approximately 28% of missing proteins (46 of 162) on Chr 9 compared with the list of missing proteins from the neXtProt Master Table (2013-09). In addition, we performed a comparative proteomics analysis between normal lung and lung cancer tissues. On the basis of the data analysis, 15 proteins from Chr 9 were detected only in lung cancer tissues. Finally, we conducted a proteogenomic analysis to discover Chr 9-residing single nucleotide polymorphisms (SNP) and mutations described in the COSMIC cancer mutation database. We identified 21 SNPs and four mutations containing peptides on Chr 9 from normal human cells/tissues and lung cancer cell lines, respectively. In summary, this study provides valuable information of the human proteome for the scientific community as part of C-HPP. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium with the data set identifier PXD000603.


Asunto(s)
Cromosomas Humanos Par 9 , Genoma Humano , Neoplasias Pulmonares/genética , Proteoma , Humanos , Mutación , Polimorfismo de Nucleótido Simple
14.
Am J Emerg Med ; 32(11): 1305-10, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25249338

RESUMEN

OBJECTIVES: In an attempt to begin ST-segment elevation myocardial infarction (STEMI) treatment more quickly (referred to as door-to-balloon [DTB] time) by minimizing preventable delays in electrocardiogram (ECG) interpretation, cardiac catheterization laboratory (CCL) activation was changed from activation by the emergency physician (code heart I) to activation by a single page if the ECG is interpreted as STEMI by the ECG machine (ECG machine auto-interpretation) (code heart II). We sought to determine the impact of ECG machine auto-interpretation on CCL activation. METHODS: The study period was from June 2010 to May 2012 (from June to November 2011, code heart I; from December 2011 to May 2012, code heart II). All patients aged 18 years or older who were diagnosed with STEMI were evaluated for enrollment. Patients who experienced the code heart system were also included. Door-to-balloon time before and after code heart system were compared with a retrospective chart review. In addition, to determine the appropriateness of the activation, we compared coronary angiography performance rate and percentage of STEMI between code heart I and II. RESULTS: After the code heart system, the mean DTB time was significantly decreased (before, 96.51 ± 65.60 minutes; after, 65.40 ± 26.40 minutes; P = .043). The STEMI diagnosis and the coronary angiography performance rates were significantly lower in the code heart II group than in the code heart I group without difference in DTB time. CONCLUSION: Cardiac catheterization laboratory activation by ECG machine auto-interpretation does not reduce DTB time and often unnecessarily activates the code heart system compared with emergency physician-initiated activation. This system therefore decreases the appropriateness of CCL activation.


Asunto(s)
Cateterismo Cardíaco , Electrocardiografía , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/terapia , Servicio de Cardiología en Hospital , Angiografía Coronaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Tiempo de Tratamiento , Resultado del Tratamiento
15.
Ecol Evol ; 13(12): e10792, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38077507

RESUMEN

Climatic fluctuations and geological events since the LGM are believed to have significantly impacted the population size, distribution, and mobility of many species that we observe today. In this paper, we determined the processes driving the phylogeographic structure of the Korean endemic white forsythia by combining the use of genome-wide SNPs and predicting paleoclimatic habitats during the LGM (21 kya), Early Holocene (10 kya), Mid-Holocene (6 kya), and Late Holocene (3 kya). Using a maximum of 1897 SNPs retrieved from 124 samples across nine wild populations, five environmental predictors, and the species' natural occurrence records, we aimed to infer the species' demographic history and reconstruct its possible paleodistributions with the use of approximate Bayesian computation and ecological niche models, respectively. Under this integrated framework, we found strong evidence for patterns of range shift and expansion, and population divergence events from the onset of the Holocene, resulting in the formation of its five distinct genetic units. The most highly supported model inferred that after the split of an ancestral population into the southern group and a larger central metapopulation lineage, the latter gave rise to the eastern and northern clusters, before finally dividing into two sub-central groups. While the use of molecular data allowed us to identify and refine the (phylo)genetic relationships of the species' lineages and populations, the use of ecological data helped us infer a past LGM refugium and the directions of post-glacial range dynamics. The time frames of these demographic events were shown to be congruent with climatic and geological events that affected the central Korean Peninsula during these periods. These findings gave us a better understanding of the consequences of past spatiotemporal factors that may have resulted in the current fragmented population distribution of this endangered plant.

16.
Sci Rep ; 13(1): 22303, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102231

RESUMEN

In this study, numerical simulation was employed to predict the performance and internal flow characteristics of the inlet of an axial-flow pump by assigning an absolute flow angle to the inlet guide vane (IGV) trailing-edge flow. Further, the finite volume method based on the three-dimensional Reynolds-averaged Navier-Stokes equations was employed to discretize the governing equations. The shear stress transport model was used as the turbulence model, and an appropriate number of nodes were selected for the hexahedral grid system through a grid-dependency test. The performance curve and changes in the internal flow field were investigated based on the variation in the flow angle at the inlet of the axial-flow pump. These results can be used to establish an efficient operational plan by adjusting the IGV angle of IGV when installing a variable IGV for an axial-flow pump.

17.
Plants (Basel) ; 12(7)2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37050109

RESUMEN

Caulophyllum robustum, commonly named Asian blue cohosh, is a perennial herb in the family Berberidaceae. It has traditionally been used for folk medicine in China. We isolated berberine from the leaves, stem, roots, and fruits of C. robustum, and this is the first report on berberine in this species. Transcriptome analysis was conducted for the characterization of berberine biosynthesis genes in C. robustum, in which, all the genes for berberine biosynthesis were identified. From 40,094 transcripts, using gene ontology (GO) analysis, 26,750 transcripts were assigned their functions in the categories of biological process, molecular function, and cellular component. In the analysis of genes expressed in different tissues, the numbers of genes in the categories of intrinsic component of membrane and transferase activity were up-regulated in leaves versus stem. The berberine synthesis genes in C. robustum were characterized by phylogenetic analysis with corresponding genes from other berberine-producing species. The co-existence of genes from different plant families in the deepest branch subclade implies that the differentiation of berberine synthesis genes occurred early in the evolution of berberine-producing plants. Furthermore, the copy number increment of the berberine synthesis genes was detected at the species level.

18.
Nat Commun ; 14(1): 685, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36755020

RESUMEN

Constructing a mono-atom step-level ultra-flat material surface is challenging, especially for thin films, because it is prohibitively difficult for trillions of clusters to coherently merge. Even though a rough metal surface, as well as the scattering of carriers at grain boundaries, limits electron transport and obscures their intrinsic properties, the importance of the flat surface has not been emphasised sufficiently. In this study, we describe in detail the initial growth of copper thin films required for mono-atom step-level flat surfaces (MSFSs). Deposition using atomic sputtering epitaxy leads to the coherent merging of trillions of islands into a coplanar layer, eventually forming an MSFS, for which the key factor is suggested to be the individual deposition of single atoms. Theoretical calculations support that single sputtered atoms ensure the formation of highly aligned nanodroplets and help them to merge into a coplanar layer. The realisation of the ultra-flat surfaces is expected to greatly assist efforts to improve quantum behaviour by increasing the coherency of electrons.

19.
Nanotechnology ; 23(25): 255301, 2012 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-22652564

RESUMEN

Mushroom-shaped phase change memory (PCM) consisting of a Cr/In(3)Sb(1)Te(2) (IST)/TiN (bottom electrode) nanoarray was fabricated via block copolymer lithography and single-step dry etching with a gas mixture of Ar/Cl(2). The process was performed on a high performance transparent glass-fabric reinforced composite film (GFR Hybrimer) suitable for use as a novel substrate for flexible devices. The use of GFR Hybrimer with low thermal expansion and flat surfaces enabled successful nanoscale patterning of functional phase change materials on flexible substrates. Block copolymer lithography employing asymmetrical block copolymer blends with hexagonal cylindrical self-assembled morphologies resulted in the creation of hexagonal nanoscale PCM cell arrays with an areal density of approximately 176 Gb/in(2).

20.
Sci Rep ; 12(1): 15240, 2022 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-36085157

RESUMEN

The stall in an axial fan is directly related to detrimental phenomena such as performance degradation, vibration, noise, and flow instability at low flow rates. As a kind of passive control method to handle the stall, two-dimensional plates so-named anti-stall fin (ASF) were suggested by ourselves and were attached inside the casing. In this study, the ASF's effect on the internal flow pattern was visually investigated in the flow passage, and its tendency was discussed with the performance curve. Subsequently, the ASF's functional limitations for various design parameters, which the ASF can derive aerodynamically, were presented as the primary focus of this study. Each one-factor analysis was performed, and the internal flow pattern was observed in parallel at the point where the ASF lost its function. For the radial length, axial length, number of fins, and positive-tangential angle, the ASF almost retained its function up to the limitation to prevent instability but radically lost its function at a certain flow rate. For the axial gap and negative-tangential angle, the ASF gradually lost its function. Mostly, this study was based on numerical analysis, and the performance was validated through experimental tests.


Asunto(s)
Fiebre Porcina Africana , Osteopatía , Aletas de Animales , Animales , Análisis Factorial , Arteria Radial , Porcinos
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