25 research outputs found

    The Volume of Hippocampal Subfields in Relation to Decline of Memory Recall Across the Adult Lifespan

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    Background: The hippocampus is an important limbic structure closely related to memory function. However, few studies have focused on the association between hippocampal subfields and age-related memory decline. We investigated the volume alterations of hippocampal subfields at different ages and assessed the correlations with Immediate and Delayed recall abilities.Materials and Methods: A total of 275 participants aged 20–89 years were classified into 4 groups: Young, 20–35 years; Middle-early, 36–50 years; Middle-late, 51–65 years; Old, 66–89 years. All data were acquired from the Dallas Lifespan Brain Study (DLBS). The volumes of hippocampal subfields were obtained using Freesurfer software. Analysis of covariance (ANCOVA) was performed to analyze alterations of subfield volumes among the 4 groups, and multiple comparisons between groups were performed using the Bonferroni method. Spearman correlation with false discovery rate correction was used to investigate the relationship between memory recall scores and hippocampal subfield volumes.Results: Apart from no significant difference in the left parasubiculum (P = 0.269) and a slight difference in the right parasubiculum (P = 0.022), the volumes of other hippocampal subfields were significantly different across the adult lifespan (P < 0.001). The hippocampal fissure volume was increased in the Old group, while volumes for other subfields decreased. In addition, Immediate recall scores were associated with volumes of the bilateral molecular layer, granule cell layer of the dentate gyrus (GC-DG), cornus ammonis (CA) 1, CA2/3, CA4, left fimbria and hippocampal amygdala transition area (HATA), and right fissure (P < 0.05). Delayed recall scores were associated with the bilateral molecular layer, GC-DG, CA2/3 and CA4; left tail, presubiculum, CA1, subiculum, fimbria and HATA (P < 0.05).Conclusion: The parasubiculum volume was not significantly different across the adult lifespan, while atrophy in dementia patients in some studies. Based on these findings, we speculate that volume changes in this region might be considered as a biomarker for dementia disorders. Additionally, several hippocampal subfield volumes were significantly associated with memory scores, further highlighting the key role of the hippocampus in age-related memory decline. These regions could be used to assess the risk of memory decline across the adult lifespan

    Field Manipulations in On-Chip Micro/Nanoscale Lasers Based on Colloid Nanocrystals

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    Owning to merits such as bandgap tunability, solution processability, large absorption coefficients, and high photoluminescence quantum yields, colloidal quantum dots (CQDs) emerged as a promising gain material to make on-chip micro/nanoscale lasers with high silicon compatibility. In this paper, we review the recent progress in CQD on-chip micro/nanoscale lasers, with a special focus on the physical properties achieved through field manipulation schemes in different types of cavities. Key aspects include manipulating and engineering wavelength, polarization, and direction as well as coupling and light extraction. Finally, we give our prospects for future research directions toward the integration of robust CQD nano/microscale lasers with photonic integrated circuits

    Supplementary document for High-purity and wide-angle reflective structural colors based on an all-dielectric Fabry-Pérot cavity structure - 6791252.pdf

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    Sample Preparation for SEM;Angle Behaviors of the DeviceBlue and Green Device DesignsOptical Constants of Materials

    Incorporation of Copper Enhances the Anti-Ageing Property of Flame-Sprayed High-Density Polyethylene Coatings

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    High-density polyethylene (HDPE)-copper (Cu) composite coatings were prepared through depositing HDPE-Cu core-shell particles by flame spraying. The HDPE-Cu composite coatings and the HDPE coatings were aged in xenon lamp ageing testing chamber. The variations of chemical compositions and surface morphology of the coatings before and after the ageing testing were analyzed using infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and ultraviolet-visible spectrophotometer. Results show that there is no chemical composition variation in the HDPE-Cu coatings. Cracks were found on the surfaces of the HDPE coatings, while the HDPE-Cu coating shows almost intact surface morphology. These results suggest that the HDPE-Cu coatings present better anti-ageing performances than the HDPE coatings. Further assessment of the function of Cu shells on the anti-ageing property reveals that Cu shells not only enhanced the absorption of the coatings to ultraviolet, but also increased their reflectivity to visible light. Additionally, the Cu shells enhanced the decomposition temperature and thermal stability of HDPE in the composite coatings. These results give bright insight into potential anti-ageing applications of the polymer-based structures

    Semi-flipped classroom-based learning interventions in a traditional curriculum of oral medicine: students’ perceptions and teaching achievements

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    Abstract Background In recent years, flipped classes have emerged and become popular in college medical education. However, due to the huge medical learning system and the limited pre-class study time of students, it is difficult to implement in all courses. And then we adopted the semi-flipped classes (SFCs) to evaluate its teaching effect. This study analysed three educational methods that can be used in oral medicine courses: online education, offline education, and semi-flipped classes. Methods We used two surveys to evaluate the three educational methods. In the first survey 46 teachers and 238 undergraduates shared their experience of the live-streaming and traditional offline courses offered in the different oral medicine curricula; we used anonymous questionnaires to evaluate their class experience. In the second survey 94 students shared their experience of the semi-flipped and traditional classrooms. Students who attended the SFCs in the experimental group learned about the oral mucosa disease by themselves using an online video course and then participated in offline interaction with teachers. The evaluation of the above educational methods was conducted using the anonymous questionnaires and final exam assessment. Results According to the first survey, teachers and students both agreed that the overall teaching experience and learning effectiveness in offline education are superior to those in online education. According to the second survey, students who participated in the SFCs performed better in the final exam than those who participated in the simple offline classes. Additionally, the survey showed that the new teaching method helped students gain more knowledge and positively influenced their clinical practice. Conclusions Compared with the online and offline educational methods, the SFC showed better results in both the questionnaire and final exam assessment. Hence, the effectiveness of medical education can be improved by adopting a teaching mode that combines online and offline teaching methods. Scientific and logical SFCs designs, along with their effective implementation, would eventually make SFCs an important tool for medical education

    The efficacy and safety of low-dose rituximab in immune thrombocytopenia: a systematic review and meta-analysis

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    Rituximab has been frequently used as a second-line treatment for patients with immune thrombocytopenia (ITP). Recently, several studies have proposed low-dose (100 mg or 100mg/m2 per week for 4 weeks) rituximab instead of the standard dose of 375mg/m2 per week for 4 weeks to treat ITP patients. The aim of this review was to systematically evaluate the efficacy and safety of low-dose rituximab for patients with ITP. Pubmed, Web of Science, Cochrane Library and Embase were searched to identify the clinical studies published in full text or abstract that met the predefined inclusion criteria. Efficacy analysis was restricted to the studies enrolling five or more patients. While safety analysis was evaluated based on all the studies reported adverse events. Nine studies (329 patients) were included for effect assessment of low-dose rituximab treatment on the patients with ITP. The pooled overall response rate was 63% (95% CI, 0.54–0.71) while the pooled complete response was 44% (95% CI, 0.33–0.55). Thirty-one patients were reported to experience adverse effects associated with rituximab, among them 30 cases suffered mild to moderate side-effects (grade1-2). Only one patient developed into interstitial pneumonia (grade3). No death was reported. Low-dose rituximab exhibited a satisfactory efficacy and safety profile, indicating that this regimen is a promising therapy for ITP, and should be further investigated through randomized clinical trials with standard-dose rituximab

    The picture of undergraduate dental basic research education: a scoping review

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    Abstract Background Undergraduate dental basic research education (UDBRE) is broadly regarded as an important approach for cultivating scientific research talent. This scoping review aims to summarize the current status of UDBRE in terms of educational goals, teaching program and content, assessment system, training outcomes, barriers, and reflections. Methods The authors performed a systematic literature search in PubMed, Web of Science, and Education Resources Information Center (ERIC) to identify peer-reviewed articles written in English from their inception to January 29, 2021. Articles were reviewed and screened according to the inclusion and exclusion criteria. Related data from the included publications were then collected and summarized. Results The authors searched 646 publications and selected 16 articles to include in the study. The education goals included cultivating five major dental basic research capabilities (n=10, 62.5%) and developing interest in basic research (n=2, 12.5%). As for the teaching program, the mentor-guided student research project was the most popular (n=11, 68.8%), followed by didactic courses (n=5, 31.3%), experimental skills training (n=1, 6.3%), and the combination of the above forms (n=3, 18.8%). However, the assessment system and training outcome diverged. Existing evidence showed that UDBRE reached satisfying education outcomes. Barriers included excessive curriculum burden (n=2, 12.5%), tutor shortage (n=3, 18.8%), lack of financial support (n=5, 31.3%), and inadequate research skills and knowledge (n=5, 31.3%). Conclusions Although efforts were made, the variation between studies revealed the immature status of UDBRE. A practical UDBRE education system paradigm was put forward. Meanwhile, more research is required to optimize a robust UDBRE system with clear education goals, well-designed teaching forms, and convincing assessment systems

    Genome-wide identification, structural and gene expression analysis of the bZIP transcription factor family in sweet potato wild relative Ipomoea trifida

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    Abstract Background The basic leucine zipper (bZIP) transcription factor is one of the most abundant and conserved transcription factor families. In addition to being involved in growth and development, bZIP transcription factors also play an important role in plant adaption to abiotic stresses. Results A total of 41 bZIP genes that encode 66 proteins were identified in Ipomoea trifida. They were distributed on 14 chromosomes of Ipomoea trifida. Segmental and tandem duplication analysis showed that segmental duplication played an important role in the ItfbZIP gene amplification. ItfbZIPs were divided into ten groups (A, B, C, D, E, F, G, H, I and S groups) according to their phylogenetic relationships with Solanum lycopersicum and Arabidopsis thaliana. The regularity of the exon/intron numbers and distributions is consistent with the group classification in evolutionary tree. Prediction of the cis-acting elements found that promoter regions of ItfbZIPs harbored several stress responsive cis-acting elements. Protein three-dimensional structural analysis indicated that ItfbZIP proteins mainly consisted of α-helices and random coils. The gene expression pattern from transcriptome data and qRT-PCR analysis showed that ItfbZIP genes expressed with a tissue-specific manner and differently expressed under various abiotic stresses, suggesting that the ItfbZIPs were involved in stress response and adaption in Ipomoea trifida. Conclusions Genome-wide identification, gene structure, phylogeny and expression analysis of bZIP gene in Ipomoea trifida supplied a solid theoretical foundation for the functional study of bZIP gene family and further facilitated the molecular breeding of sweet potato
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