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1.
Curr Psychol ; : 1-14, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35039738

RESUMO

The COVID-19 pandemic caused school closures and social isolation, which created both learning and emotional challenges for adolescents. Schools worked hard to move classes online, but less attention was paid to whether students were cognitively and emotionally ready to learn effectively in a virtual environment. This study focused on online learning readiness and emotional competence as key constructs to investigate their implications for students' academic performance during the COVID-19 period. Two groups of students participated in this study, with 1,316 high school students (Mean age = 16.32, SD = 0.63) representing adolescents and 668 college students (Mean age = 20.20, SD = 1.43) representing young adults. Structural equation modeling was conducted to explore the associations among online learning readiness, emotional competence, and online academic performance during COVID-19 after controlling for pre-COVID-19 academic performance. The results showed that, for high school students, both online learning readiness and emotional competence were positively associated with online academic performance during COVID-19. However, for college students, only online learning readiness showed a significant positive relationship with online academic performance during COVID-19. These results demonstrated that being ready to study online and having high emotional competence could make adolescents more resilient toward COVID-19-related challenges and help them learn more effectively online. This study also highlighted different patterns of associations among cognitive factors, emotional factors, and online academic performance during COVID-19 in adolescence and young adulthood. Developmental implications were also discussed.

2.
BMC Plant Biol ; 20(1): 182, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32334538

RESUMO

BACKGROUND: Propagation of cuttings is frequently used in various plant species, including blueberry, which shows special root characteristics that may hinder adventitious root (AR) formation. AR formation is influenced by various factors, and auxin is considered to play a central role; however, little is known of the related regulatory mechanisms. In this study, a comparative transcriptome analysis of green cuttings treated with or without indole-butyric acid (IBA) was performed via RNA_seq to identify candidate genes associated with IBA-induced AR formation. RESULTS: Rooting phenotypes, especially the rooting rate, were significantly promoted by exogenous auxin in the IBA application. Blueberry AR formation was an auxin-induced process, during which adventitious root primordium initiation (rpi) began at 14 days after cutting (DAC), root primordium (rp) was developed at 21 DAC, mature AR was observed at 28 DAC and finally outgrowth from the stem occurred at 35 DAC. Higher IAA levels and lower ABA and zeatin contents might facilitate AR formation and development. A time series transcriptome analysis identified 14,970 differentially expressed genes (DEGs) during AR formation, of which there were 7467 upregulated and 7503 downregulated genes. Of these, approximately 35 candidate DEGs involved in the auxin-induced pathway and AR formation were further identified, including 10 auxin respective genes (ARFs and SAURs), 13 transcription factors (LOB domain-containing protein (LBDs)), 6 auxin transporters (AUX22, LAX3/5 and PIN-like 6 (PIL6s)) and 6 rooting-associated genes (root meristem growth factor 9 (RGF9), lateral root primordium 1 (LRP1s), and dormancy-associated protein homologue 3 (DRMH3)). All these identified DEGs were highly upregulated in certain stages during AR formation, indicating their potential roles in blueberry AR formation. CONCLUSIONS: The transcriptome profiling results indicated candidate genes or major regulatory factors that influence adventitious root formation in blueberry and provided a comprehensive understanding of the rooting mechanism underlying the auxin-induced AR formation from blueberry green cuttings.


Assuntos
Mirtilos Azuis (Planta)/genética , Genes de Plantas , Raízes de Plantas/genética , Mirtilos Azuis (Planta)/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Ácidos Indolacéticos/metabolismo , Indóis/farmacologia , Fenótipo , Reguladores de Crescimento de Plantas/análise , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , RNA de Plantas , RNA-Seq , Transdução de Sinais
3.
Heart Vessels ; 34(8): 1332-1339, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30848337

RESUMO

The variable anatomy of Ebstein's anomaly leads to its various surgical procedures. The long-term outcomes of different operations were not well established. Thirty-five patients with Ebstein's anomaly who underwent operations from 2006 to 2018 in our department were retrospectively reviewed. Individualized surgical plans were performed according to the preoperative echocardiography and surgeons' preference. Tricuspid repair, either Danielson's or Carpentier's technique, was the primary choice in patients who had sufficient tricuspid leaflets and adequate right ventricle, while tricuspid replacement was used when a reliable repair is not achievable. Additional bidirectional cavopulmonary shunt was performed in those who had unstable hemodynamics despite of high central venous pressure after separation from cardiopulmonary bypass. The perioperative and follow-up data were collected. The age was 26.9 (0.6-54) years [16 children (age < 14, and 19 adults (age ≥ 14)]. Preoperative tricuspid regurgitation was severe in 30, moderate in 4, and mild in the remaining 1 patient. Preoperative cardiac-associated malformations include 20 atrial septal defects, 2 ventricular septal defects, 2 pulmonary stenosis, and 1 sub aortic ridge, and these were operated simultaneously. Among all the surgical patients, 2 needed additional reoperation during the same admission, and ultimately, 29 patients had biventricular repair, including 21 tricuspid repair and 8 replacements. The other 6 patients had cavopulmonary connection and achieved 1.5 ventricular repair (3 tricuspid repair and 3 replacements). In all the 24 tricuspid repair patients, Danielson's procedure was used in 17, while Carpentier's technique was used in the other 7 patients. The average cardiopulmonary bypass time was 90 ± 28 min and cross-clamp time was 48 ± 24min. There were 2 perioperative deaths (5.7%) and no third-degree atrioventricular block. The postoperative in hospital stay was 13.7 ± 9.6 days. In the 33 survivors who were followed up at a median of 29.2 months, 6 patients had severe tricuspid regurgitation, and 2 of them underwent tricuspid replacement. The 5-year freedom from severe tricuspid dysfunction or reoperation was 78.5%, and no difference was found between children and adults, neither between different surgical choices. The surgeries of Ebstein's anomaly were variable, and individualized operation achieved reasonable short- and mid-term results. However, severe tricuspid regurgitation during the follow-up was not neglectable, and reoperation in such cases also achieved good outcomes. New repair strategy such as cone repair may be considered.


Assuntos
Anuloplastia da Valva Cardíaca , Anomalia de Ebstein/cirurgia , Técnica de Fontan , Adolescente , Adulto , Ponte Cardiopulmonar , Criança , Pré-Escolar , Anomalia de Ebstein/mortalidade , Anomalia de Ebstein/fisiopatologia , Ecocardiografia , Feminino , Humanos , Masculino , Reoperação , Estudos Retrospectivos , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/fisiopatologia , Função Ventricular Direita , Adulto Jovem
4.
Front Cell Infect Microbiol ; 13: 1321626, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259974

RESUMO

Objectives: Staphylococcal small-colony variants (SCVs) are common in cardiac implantable electronic device (CIED) infections. This is the first retrospective and multi-case study on CIED infections due to staphylococcal SCVs, aiming to provide a theoretical basis for the clinical management of CIED and device-related infections caused by staphylococcal SCVs. Methods: Ninety patients with culture positive CIED infections were enrolled between 2021 and 2022. We compared the demographic and clinical characteristics of patients with and without SCVs and performed genomic studies on SCVs isolates. Results: Compared to patients without SCVs, those with SCVs had a longer primary pacemaker implantation time and were more likely to have a history of device replacement and infection. They showed upregulated inflammatory indicators, especially higher NEUT% (52.6 vs. 26.8%, P = 0.032) and they had longer hospital stays (median 13 vs. 12 days, P = 0.012). Comparative genomics analysis was performed on Staphylococcus epidermidis wild-type and SCVs. Some genes were identified, including aap, genes encoding adhesin, CHAP domain-containing protein, LPXTG cell wall anchor domain-containing protein, and YSIRK-type signal peptide-containing protein. Conclusion: Staphylococcal SCVs affect the clinical characteristics of CIED infections. The process of staphylococcal SCVs adherence, biofilm formation, and interaction with neutrophils play a vital role.


Assuntos
Doenças Transmissíveis , Genômica , Humanos , Estudos Retrospectivos , Staphylococcus , Staphylococcus epidermidis/genética , Eletrônica
5.
Chemphyschem ; 13(1): 336-41, 2012 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-22095763

RESUMO

Magnetic iron oxide particles are widely used as contrast agents to improve the sensitivity of magnetic resonance imaging (MRI). Their efficiency in MRI is usually quantified by transverse relaxivity (r(2)) in solution. Herein, we synthesized a series of magnetite nanocrystal clusters (MNCs) with ultra-high transverse relaxivity by a polyol process and studied the relationship between r(2) and size of the MNCs. The sizes of MNCs can be tuned over a wide range from 13 to 179 nm. The r(2) of MNC suspensions as a function of the size of the cluster was analyzed and compared with a theoretical model. We found that MNCs of 64 nm had an r(2) value of 650 mM(-1) s(-1), which was more than three times that of the commercial contrast agent and was among the highest reported for iron oxide materials. Compared with the theoretical model, the r(2) value of the MNC suspension is approximately 0.93 of the theoretical prediction. Imaging of the MNC suspensions was performed in a clinical 1.5 T MRI instrument and a comparison was made between MNCs and commercial contrast agents. MRI indicated that the decrease of signal intensity induced by MNCs was in proportion to the r(2) value, which was in accordance with theoretical predictions. These results demonstrate that MNCs with ultra-high transverse relaxivity and tunable size are promising candidates for molecular imaging and clinical diagnosis in MRI.


Assuntos
Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Compostos Férricos/química , Modelos Teóricos , Polímeros/química
6.
Front Plant Sci ; 13: 944269, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937353

RESUMO

Loquat (Eriobotrya japonica Lindl. ) is one of the most economically important evergreen fruit crops in China, while it often suffered the injury of cold stress in winter and earlier spring, and the annual yield loss of loquat fruits caused by cold or freezing stress was immeasurable. However, knowledge about the physiological response and molecular mechanism under cold stress is still limited. To investigate the potential regulation mechanism pre- and post-cold stress in loquat and the changes in physiological indicators, a comparative transcriptome analysis was performed against a cold-resistant cv. "Huoju" and a cold-sensitive cv. "Ninghaibai". The results of physiological indicators related to cold resistance indicated that rachis was most sensitive to cold stress and was considered as the representative organ to directly evaluate cold resistance of loquat based on subordinate function analysis. Here, we compared the transcriptome profiles of rachis pre- and under cold stress in "Huoju" and "Ninghaibai". A total of 4,347 and 3,513 differentially expressed genes (DEGs) were detected in "Ninghaibai" and "Huoju", among which 223 and 166 were newly identified genes, respectively, most of them were functionally enriched in plant hormone signal transduction (Huoju: 142; Ninghaibai: 200), and there were higher plant hormone content and related DEG expression levels in "Huoju" than that of "Ninghaibai". Moreover, a total of 3,309 differentially expressed transcription factors (DETFs) were identified, and some DEGs and DETFs were screened to be subjected to co-expression network analysis based on the gene expression profile data. Some candidate DEGs, including UDP-glycosyltransferase (UGT), glycosyltransferase (GT), sugar phosphate/phosphate translocator (SPT), sugar transport protein (STP), proline-rich receptor-like protein kinase (PERK), and peroxidise (POD), were significantly affected by cold stress, and the expression level of these genes obtained from real-time quantitative RT-PCR was consistent with the pattern of transcriptome profile, which suggested that these genes might play the vital roles in cold resistance of loquat. Our results provide an invaluable resource for the identification of specific genes and TFs and help to clarify gene transcription during the cold stress response of loquat.

7.
Gigascience ; 9(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32141509

RESUMO

BACKGROUND: The loquat (Eriobotrya japonica) is a species of flowering plant in the family Rosaceae that is widely cultivated in Asian, European, and African countries. It blossoms in the winter and ripens in the early summer. The genome of loquat has to date not been published, which limits the study of molecular biology in this cultivated species. Here, we used the third-generation sequencing technology of Nanopore and Hi-C technology to sequence the genome of Eriobotrya. FINDINGS: We generated 100.10 Gb of long reads using Oxford Nanopore sequencing technologies. Three types of Illumina high-throughput sequencing data, including genome short reads (47.42 Gb), transcriptome short reads (11.06 Gb), and Hi-C short reads (67.25 Gb), were also generated to help construct the loquat genome. All data were assembled into a 760.1-Mb genome assembly. The contigs were mapped to chromosomes by using Hi-C technology based on the contacts between contigs, and then a genome was assembled exhibiting 17 chromosomes and a scaffold N50 length of 39.7 Mb. A total of 45,743 protein-coding genes were annotated in the Eriobotrya genome, and we investigated the phylogenetic relationships between the Eriobotrya and 6 other Rosaceae species. Eriobotrya shows a close relationship with Malus and Pyrus, with the divergence time of Eriobotrya and Malus being 6.76 million years ago. Furthermore, chromosome rearrangement was found in Eriobotrya and Malus. CONCLUSIONS: We constructed the first high-quality chromosome-level Eriobotrya genome using Illumina, Nanopore, and Hi-C technologies. This work provides a valuable reference genome for molecular studies of the loquat and provides new insight into chromosome evolution in this species.


Assuntos
Cromossomos de Plantas/genética , Eriobotrya/genética , Genoma de Planta , Mapeamento Cromossômico , Eriobotrya/classificação , Anotação de Sequência Molecular , Sequenciamento por Nanoporos , Filogenia , Sequenciamento Completo do Genoma
8.
Genes Genomics ; 42(4): 383-392, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31902111

RESUMO

BACKGROUND: Parthenocarpy can be induced by gibberellin (GA) treatment in plants. The fruits of the loquat exhibit many seeds. GA treatment can induce the development of seedless fruit and increase fruit quality during production. However, the molecular mechanism of fruit setting under GA treatment is still unclear. OBJECTIVE: Our aim was to explore GA-induced parthenocarpy in triploid loquat by proteome analysis to identify the differentially expressed proteins. METHODS: A proteome analysis was performed using TMT protein labeling and LC-MS/MS in triploid loquat. RESULTS: A total of 7290 protein groups were identified in the two stages of fruit setting. The quantitative results showed that 923 differentially expressed proteins (DEPs) were isolated, which were enriched in five pathways: ribosome, citrate cycle (TCA cycle), pentose phosphate, carbon metabolism, and carbon fixation. Twenty-four DEPs were annotated as putative key regulatory proteins involved in fruit setting, which were related to the auxin response, gibberellin metabolism, ethylene synthesis, and cell division. In addition, thirty-five DEPs were involved in the formation of the cell wall, which might be downstream proteins involved in cell proliferation during fruit setting. CONCLUSION: Our report reveals new insight into the protein dynamics of loquat fruit setting induced by GA treatment via the analysis of proteome profiles and provides a reference for other Rosaceae species.


Assuntos
Eriobotrya/metabolismo , Giberelinas/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Sementes/metabolismo , Eriobotrya/genética , Eriobotrya/fisiologia , Proteínas de Plantas/genética , Proteoma/genética , Sementes/genética , Sementes/fisiologia , Triploidia
9.
Sci Rep ; 10(1): 1033, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31974494

RESUMO

Grafting is a common method of variety propagation in loquat breeding, the slow growth of rootstocks is a main factor limiting the expansion of this technique. This study aimed to evaluate the effects of seven different fertilizer formulas on the growth of loquat rootstock seedlings, five water-soluble fertilizer formulas, as well as organic fertilizer and controlled-release fertilizer were evaluated. An unfertilized control (CK) was also performed. Growth indicators including plant height, stem thickening and lignification, leaf area, root development, dry matter accumulation, spatial distribution of nutrient elements, and cross-sectional anatomy of stem were measured. The results showed that the addition of microelements in fertilizer could significantly delay the lignification process of the cambium, which exhibiting the greatest improvement in stem thickening. Phosphorus nutrition could significantly promote the occurrence of fibrous roots, while excessive phosphorus supply might disturb the absorption and utilization of nitrogen of roots, intensify the lignification process of the main stem, and then affect the growth of the aboveground part. The findings of this research could provide a theoretical basis for identifying an optimum fertilization formula and technique for promoting the rapid growth and accelerating the lignification process at different stages of loquat rootstock seedling growth.

10.
Nanotechnology ; 20(40): 405102, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19752494

RESUMO

Silica coated, PEI and citric acid hybrid superparamagnetic magnetite nanocrystal clusters (SMNC) were synthesized using either a mini-emulsion/sol-gel method or a polyol technique. After careful characterization of the size, structure, composition, and magnetic properties, the as-synthesized SMNC were used for cell labeling while the MR detection sensitivity of cells labeled with silica SMNC was performed with a 3 T whole body MR scanner. TEM investigations revealed that the sizes of the SMNC were about 200 nm and the SMNC mainly consisted of magnetite nanoparticles imbedded in a PEI, citric acid or polystyrene scaffold. Silica and citric acid SMNC were highly negatively charged and PEI SMNC were positively charged. Relaxometry measurements revealed that these SMNC possessed a very high MR sensitivity (silica SMNC: r(2) = 299 s(-1) mM(-1), PEI SMNC: r(2) = 124 s(-1) mM(-1)), especially for the citric acid SMNC (r(2) = 360 s(-1) mM(-1)). Furthermore, when used for cell (RAW264.7 cells) labeling, the SMNC had no adverse effect on cell viability, and the cell uptake of the SMNC show a dose- and time-dependent feature. MR imaging of cells labeled with silica SMNC indicated that cells with a concentration as low as 10 x 10(3) cells ml(-1) could be detected with a 3 T MRI scanner. Our study demonstrated that superparamagnetic magnetite nanocrystal clusters are a sensitive tool for cell imaging.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Magnetismo , Nanopartículas/química , Animais , Linhagem Celular , Ácido Cítrico/química , Camundongos , Microscopia Eletrônica de Transmissão , Nanopartículas/ultraestrutura , Polietilenoimina/química , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier
11.
ACS Appl Mater Interfaces ; 11(1): 1192-1200, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30565450

RESUMO

Semiconductor nanowires are the ideal building blocks to construct various thin-film electronic and optoelectronic devices, the performance of which is largely determined by their ensemble geometry and surface chemistry in addition to the chemical composition. Here, we report the large-scale and oriented assembly of CdSe nanowires on the basis of a light-induced assembly approach under an external electric field. To further increase the electrical conductivity of nanowire films, the original surface-capping organic ligands are exchanged with small ionic species through a solid-state ligand-exchange process. The resulting surface-modified CdSe nanowire films exhibit markedly enhanced photoresponse properties including high on/off ratios and fast response. This work establishes a simple yet scalable method to fabricate aligned nanowire films with a desired surface chemistry, which can be broadly used in various electronic and optoelectronic devices.

12.
Sci Total Environ ; 627: 462-469, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29426169

RESUMO

Aluminum (Al) toxicity associated with acid soils represents one of the biggest limitations to crop production worldwide. The root apex of plants is the major perception site of Al toxicity. In Al stressed wheat primary roots, Al accumulation and loss of plasma membrane integrity were highest in the root apex (0-5mm), and decreased along the root axis (5-25mm). To further understand these responses in wheat, spatial profiles of antioxidant responses to Al along the 0-25mm root tip of two wheat genotypes differing in Al tolerance were analyzed. Under Al stress, the lowest root elongation was in the 0-5mm root tip, and more severe inhibition was observed in Al-sensitive genotype than Al-tolerant genotype. The highest increase of Al and hydrogen peroxide (H2O2) was in the 0-5mm zone, with the most pronounced increase of malondialdehyde content and Evans blue uptake after Al exposure, especially in Al-sensitive genotype. The activities of superoxides dismutase (SOD), ascrobate peroxidase (APX), catalase (CAT) and peroxidase (POD) and levels of antioxidants (ascorbic acid, reduced glutathione, dehydroascorbate, glutathione disulfide) were significantly increased along the root tip under Al stress, with the 0-5mm region again being the most active zone. In the same zone, the activities of CAT, APX and contents of antioxidants were higher in Al-tolerant genotype while SOD and POD activities were lower. Our results indicate that Al-induced changes in H2O2 production and antioxidative system in root tip are regulated in a spatially-specific manner, suggesting that this response may play an important role in wheat adaptation to Al toxicity.


Assuntos
Alumínio/toxicidade , Estresse Oxidativo/fisiologia , Poluentes do Solo/toxicidade , Triticum/fisiologia , Antioxidantes , Catalase/metabolismo , Peróxido de Hidrogênio/metabolismo , Raízes de Plantas , Plântula , Superóxido Dismutase/metabolismo
13.
Zhonghua Wai Ke Za Zhi ; 45(20): 1411-3, 2007 Oct 15.
Artigo em Zh | MEDLINE | ID: mdl-18241596

RESUMO

OBJECTIVE: To evaluate the methods and efficacy of atrial septal defect (ASD) occlusion through right chest incision. METHODS: The clinical data of 21 patients with ASD from July 2004 to May 2005 were analyzed retrospectively. Eight patients were male and 13 patients were female, aged from 1 to 70 years old, with the median age of 21 years old. The diameter of ASD was from 8 to 40 mm. All the 21 patients were under general anaesthesia. A 2 to 3 cm incision was made in the 4th intercostals of right side of sternum. With the help of transesophageal or normal transthoracic echocardiography, the occluder was released using monotube unit. RESULTS: All cases were occluded successfully without death. The types of the occluder were from 14 to 46 mm. None failed and had to choose extracorporeal circulation operations. No transfusion and no serious complication such as the occluder dislocated occurred. And no evident of atrial shunt was found when in review echo. CONCLUSIONS: The ASD occlusion through right chest minimal incision is safe, credit, minimal invasive and worth to use widely.


Assuntos
Cateterismo Cardíaco/métodos , Comunicação Interatrial/cirurgia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Resultado do Tratamento
14.
Nanoscale ; 8(28): 13589-96, 2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27378539

RESUMO

All-inorganic cesium lead halide perovskite (CsPbX3, X = Cl, Br, and I) nanocrystals (NCs) are emerging as an important class of semiconductor materials with superior photophysical properties and wide potential applications in optoelectronic devices. So far, only a few studies have been conducted to control the shape and geometry of CsPbX3 NCs. Here we report a general approach to directly synthesize two-dimensional (2D) CsPbX3 perovskite and mixed perovskite nanosheets with uniform and ultrathin thicknesses down to a few monolayers. The key to the high-yield synthesis of perovskite nanosheets is the development of a new Cs-oleate precursor. The as-synthesized CsPbX3 nanosheets exhibit bright photoluminescence with broad wavelength tunability by composition modulation. The excellent optoelectronic properties of CsPbX3 nanosheets combined with their unique 2D geometry and large lateral dimensions make them ideal building blocks for building functional devices. To demonstrate their potential applications in optoelectronics, photodetectors based on CsPbBr3 nanosheets are fabricated, which exhibit high on/off ratios with a fast response time.

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