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1.
BMC Med Educ ; 24(1): 579, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802790

RESUMO

BACKGROUND: Among Chinese medical students, medical statistics is often perceived as a formidable subject. While existing research has explored the attitudes of Chinese postgraduate medical students towards statistics and its impact on academic performance, there is a scarcity of studies examining the attitudes of Chinese medical undergraduates on this subject. This study endeavors to scrutinize the attitudes of Chinese medical undergraduates towards statistics, assessing their ramifications on learning achievements, and delving into the influence of demographic factors. METHODS: 1266 medical undergraduates participated in this study, completing a questionnaire that included SATS-36 and additional queries. Furthermore, an examination was administered at the end of the medical statistics course. The analysis encompassed the SATS score and exam scores, examining both the overall participant population and specific demographic subgroups. RESULTS: Undergraduate medical students generally exhibit a favorable disposition towards statistics concerning Affect, Cognitive Competence, and Value components, yet harbor less favorable sentiments regarding the Difficulty component of SATS-36, aligning with previous research findings. In comparison to their postgraduate counterparts, undergraduates display heightened enthusiasm for medical statistics. However, they demonstrate a lower cognitive capacity in statistics and tend to underestimate both the value and difficulty of learning statistics. Despite these disparities, undergraduate medical students express a genuine interest in statistics and exhibit a strong dedication to mastering the subject. It is noteworthy that students' attitudes toward statistics may be influenced by their major and gender. Additionally, there exists a statistically significant positive correlation between learning achievement and the Affect, Cognitive Competence, Value, Interest, and Effort components of the SATS-36, while a negative correlation is observed with the Difficulty component. CONCLUSION: Educators should carefully consider the influence of attitudes toward statistics, especially the variations observed among majors and genders when formulating strategies and curricula to enhance medical statistics education.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , China , Estudantes de Medicina/psicologia , Masculino , Feminino , Estatística como Assunto , Adulto Jovem , Inquéritos e Questionários , Atitude do Pessoal de Saúde , Adulto
2.
Arab J Gastroenterol ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38705812

RESUMO

BACKGROUND AND STUDY AIMS: There are limited data regarding indeterminate acute liver failure (ALF). The study aims to perform a post hoc analysis using genetic methods for the ALF cases with indeterminate etiology. PATIENTS AND METHODS: Stored blood samples from these patients with indeterminate ALF were collected. Whole-exome sequencing (WES) was used to evaluate the pathogenesis of indeterminate ALF. RESULTS: A total of 16 samples from 11 adult patients and 5 pediatric patients with indeterminate ALF were available. Among the adult patients, one female patient was identified with two heterozygous variants (c.2333G > T (p.Arg778Leu) and c.2310C > G (p.Leu770 = )) in the adenosine triphosphatase copper-transporting beta (ATP7B) gene, and two male patients were found to harbor heterozygous and homozygous variants (c.686C > A (p.Pro229Gln) plus homozygousvariantA(TA)6TAAinsTA (-), andc.1456 T > G (p.Tyr486Asp) plus c.211G > A (p.Gly71Arg)) in the uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) gene. For the pediatric patients, single heterozygous variant (c.2890C > T (p.Arg964Cys)) in the polymerase gamma (POLG) gene was found in 1 male child, and two heterozygous variants (c.1909A > G (p.Lys637Glu) and c.3646G > A (p.Val1216Ile)) in the tetratricopeptide repeat domain 37 (TTC37) gene were found in 1 female child. No variants clinically associated with known liver diseases were revealed in the remaining patients. CONCLUSION: These results expand the knowledge of ALF with indeterminate etiology. WES is helpful to reveal possible candidate genes for indeterminate ALF, but incomplete consistency between the genotype and phenotype in some cases still challenge the accurate diagnosis.

3.
Angew Chem Int Ed Engl ; : e202407547, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725308

RESUMO

We report the synthesis of a longitudinally helical molecular nanocarbon, hexabenzoheptacene (HBH), along with its dimethylated derivative (HBH-Me), which are composed of six benzene rings periodically benzannulated to both zigzag edges of a heptacene core. This benzannulation pattern endows the resulting nanocarbons with a helical heptacene core and local aromaticity, imparting enhanced solubility and stability to the system. The chiral HBH-Me adopts a more highly twisted conformation with an end-to-end twist angle of 95°, enabling the separation of the enantiomers. Both HBH and HBH-Me can be facilely oxidized into their corresponding dications, which exhibit enhanced planarity and aromaticity upon loss of electrons. Notably, both longitudinally helical nanocarbons readily promote solid state packing into two-dimensional (2D) arrangement. Single-crystal microbelts of HBH-Me show hole mobility up to 0.62 cm2 V-1 s-1, illustrating the promising potential of these longitudinally helical molecules for organic electronic devices.

4.
Anal Sci ; 40(4): 765-772, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38358582

RESUMO

As one of the most fundamental thiol compounds in the human body, cysteine (Cys) is involved in maintaining redox balance. Abnormal Cys levels can lead to various diseases. In this work, we successfully synthesized a fluorescent probe (CTBA) that can specifically detect Cys using acrylate as the reaction site, and CTBA has met the selectivity and anti-interference for Cys detection under optimized conditions. The linear range for Cys detection is between 0.05 and 100 µM and the detection limit is 0.0381 µM. Finally, this probe is used to detect the Cys content in three bovine serum samples and the test results are satisfactory.


Assuntos
Cisteína , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/química , Cisteína/química , Células HeLa , Limite de Detecção , Espectrometria de Fluorescência/métodos
5.
J Clin Neurosci ; 121: 11-17, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308978

RESUMO

BACKGROUND: Nervus intermedius neuralgia (NIN) is characterized by paroxysmal episodes of sharp, lancinating pain in the deep ear. Unfortunately, only a few studies exist in the literature on this pain syndrome, its pathology and postoperative outcomes. METHOD: We conducted a retrospective review of four cases diagnosed with NIN who underwent a neurosurgical intervention at our center from January 2015 to January 2023. Detailed information on their MRI examinations, intraoperative findings and other clinical presentations were obtained, and the glossopharyngeal and vagus nerves were isolated for immunohistochemistry examination. RESULTS: A total of 4 NIN patients who underwent a microsurgical intervention at our institution were included in this report. The NI was sectioned in all patients and 3 of them underwent a microvascular decompression. Of these 4 patients, 1 had a concomitant trigeminal neuralgia (TN), and 1 a concomitant glossopharyngeal neuralgia (GPN). Three patients underwent treatment for TN and 2 for GPN. Follow-up assessments ranged from 8 to 99 months. Three patients reported complete pain relief immediately after the surgery until last follow-up, while in the remaining patient the preoperative pain gradually resolved over the 3 month period. Immunohistochemistry revealed that a greater amount of CD4+ and CD8+ T cells had infiltrated the glossopharyngeal versus vagus nerve. CONCLUSIONS: NIN is an extremely rare condition showing a high degree of overlap with TN/GPN. An in depth neurosurgical intervention is effective to completely relieve NIN pain, without any serious complications. It appears that T cells may play regulatory role in the pathophysiology of CN neuralgia.


Assuntos
Doenças do Nervo Glossofaríngeo , Cirurgia de Descompressão Microvascular , Neuralgia , Neuralgia do Trigêmeo , Humanos , Nervo Facial , Linfócitos T CD8-Positivos , Neuralgia/etiologia , Neuralgia/cirurgia , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgia , Doenças do Nervo Glossofaríngeo/cirurgia , Resultado do Tratamento
6.
Sleep Breath ; 28(1): 467-473, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37747601

RESUMO

BACKGROUND: Sleeping in an unfamiliar environment, such as a sleep laboratory, is thought to disturb sleep in healthy individuals and could express a hyperarousal state called the first night effect. Insomnia disorder (ID) is a highly prevalent health problem characterized by increased arousal during the night and daytime. Whether or not a similar phenomenon occurs in patients with ID is unclear. This study aimed to investigate the effect of an unfamiliar environment on the sleep of patients with ID. METHODS: In an unfamiliar sleep laboratory, polysomnographic recording testing was performed for two consecutive nights in patients with ID and age- and sex-matched healthy control subjects (HC). We collected sleep diaries and questionnaires regarding sleep, medical conditions, psychological status, and health history. Sleep continuity and architecture in both groups were compared and analyzed for two consecutive nights. RESULTS: Participants with ID (n = 39)  and HC (n = 35) demonstrated differentially poor sleep on laboratory adaptation after exposure to the sleep laboratory. Patients with ID had longer rapid eye movement (REM) latency on the first night than on the second sleep night. HC showed increased duration and percentage of N1, decreased duration and percentage of N3, and decreased REM percentage during initial nights compared to subsequent nights. The other sleep variables showed no differences between the first and second sleep nights in patients with ID and HC. CONCLUSIONS: An unfamiliar sleep environment does not aggravate the disruption of sleep continuity and sleep architecture but only affects the REM latency in patients with ID compared with HC.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Polissonografia , Sono , Sono REM , Nível de Alerta
7.
Angew Chem Int Ed Engl ; 62(46): e202313257, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37771246

RESUMO

The synthesis of bench-stable conjugated π-radicals is challenging owing to the lack of modular approaches, which greatly hampers their practical material screens and applications. Here, we demonstrate a spin-distribution-directed regioselective substitution strategy to introduce substituents into the specific positions of an olympicenyl radical in a stepwise manner, resulting in a series of highly stable radical species. The substituents can also adjust the crystal packing by means of steric and electronic factors, enabling the changing from a π-dimer to a pseudo-one-dimensional chain. The first single crystal organic field-effect transistor device based on a graphenic radical is fabricated in air, showing a hole mobility of up to 0.021 cm2 V-1 s-1 and excellent device stability. This approach may be generalized to diverse spin-delocalized open-shell organic radicals.

8.
Talanta ; 265: 124925, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37437396

RESUMO

The combination of highly sensitive electrochemiluminescence (ECL) techniques with localized surface plasmon resonance (LSPR) effect can achieve the highly sensitive and specific detection in the analytical and biosensing applications. However, how to effectively improve the electromagnetic field intensity is an unresolved issue. Herein, we have developed an ECL biosensor based on sulfur dots and Au@Ag nanorod array architecture. Firstly, the high luminescent sulfur dots with ionic liquid capping (S dots (IL) have been prepared as the new ECL emitter. The ionic liquid greatly improved the conductivity of sulfur dots in the sensing process. Furthermore, Au@Ag nanorods array structure was constructed on the electrode surface by the evaporation induced self-assembly. On the one hand, the LSPR of Au@Ag nanorods was more significant than that of good nanomaterial due to the plasma hybridization and the competition between free electrons and oscillating electrons. On the other hand, nanorods array structure had strong electromagnetic field intensity as hot spots due to the surface plasmon coupling ECL effect (SPC-ECL) effect. Therefore, the Au @Ag nanorods array architecture not only greatly enhanced the ECL intensity of sulfur dots, but also changed the ECL signals into polarized emission. Finally, the constructed polarized ECL sensing system was used to detect the mutated BRAF DNA in the eluent of thyroid tumor tissue. The biosensor showed the linear range from 100 fM to 10 nM with a detection limit of 20 fM. The satisfactory results demonstrated that the developed sensing strategy had great potential in the clinical diagnosis of BRAF DNA mutation in thyroid cancer.

9.
J Affect Disord ; 334: 92-99, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37149048

RESUMO

BACKGROUND: Fatigue is the most common daytime impairment of insomnia disorder (ID). Thalamus is acknowledged as the key brain region closely associated with fatigue. However, the thalamus-based neurobiological mechanisms of fatigue in patients with ID remain unknown. METHODS: Forty-two ID patients and twenty-eight well-matched healthy controls (HCs) underwent simultaneous electroencephalography--functional magnetic resonance imaging. We calculated the functional connectivity (FC) between the thalamic seed and each voxel across the whole brain in two conditions of wakefulness--after sleep onset (WASO) and before sleep onset. A linear mixed effect model was used to determine the condition effect of the thalamic FC. The correlation between daytime fatigue and the thalamic connectivity was explored. RESULTS: After sleep onset, the connectivity with the bilateral thalamus was increased in the cerebellar and cortical regions. Compared with HCs, ID patients showed significantly lower FC between left thalamus and left cerebellum under the WASO condition. Furthermore, thalamic connectivity with cerebellum under the WASO condition was negatively correlated with Fatigue Severity Scale scores in the pooled sample. CONCLUSIONS: These findings contribute to an emerging framework that reveals the link between insomnia-related daytime fatigue and the altered thalamic network after sleep onset, further highlighting the possibility that this neural pathway is a therapeutic target for meaningfully mitigating fatigue.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Vigília , Humanos , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tálamo/diagnóstico por imagem , Sono , Eletroencefalografia , Fadiga/diagnóstico por imagem
10.
Eur J Gastroenterol Hepatol ; 35(5): 600-603, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36966758

RESUMO

BACKGROUND AND OBJECTIVES: Available data regarding cardiomyopathy in patients with alcoholic liver cirrhosis (ALC) are very limited because it often requires multidisciplinary assessments. The study aims to evaluate the prevalence of alcoholic cardiomyopathy in ALC and their clinical correlations. METHODS: Adult ALC patients without a previous diagnosis of cardiovascular diseases between January 2010 and December 2019 were included in the study. The prevalence rate of alcoholic cardiomyopathy in patients with ALC was calculated together with a 95% confidence interval (CI) using the Clopper-Pearson exact method. RESULTS: A total of 1022 ALC patients were included. Male patients predominated (90.5%). ECG abnormalities were observed in 353 patients (34.5%). Prolonged QT interval was most common in ALC patients with ECG abnormalities, which occurred in 109. Thirty-five ALC patients underwent the cardiac MRI examination and only one patient was found with cardiomyopathy. The estimated prevalence rate of alcoholic cardiomyopathy in all the ALC patients was 0.0286 (95% CI, 0.0007-0.1492). There was no statistical difference regarding the prevalence rate between the group of patients with ECG abnormalities and the group without ECG abnormalities (0.0400 vs. 0.0000, P  = 1.000). CONCLUSION: Although ECG abnormalities, especially QT prolongation, existed in a proportion of ALC patients, cardiomyopathy in the patient population was not common. Further larger-sample studies based on cardiac MRI are needed to verify our results.


Assuntos
Cardiomiopatia Alcoólica , Cirrose Hepática Alcoólica , Adulto , Humanos , Masculino , Cirrose Hepática Alcoólica/complicações , Cirrose Hepática Alcoólica/diagnóstico , Cirrose Hepática Alcoólica/epidemiologia , Cardiomiopatia Alcoólica/diagnóstico , Cardiomiopatia Alcoólica/epidemiologia , Cardiomiopatia Alcoólica/complicações , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/epidemiologia
11.
Interdiscip Sci ; 15(3): 433-438, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37000408

RESUMO

Over the last few years, an increasing number of protein mis-localization events have been reported under various conditions. It is important to understand these events and their relationship with complex disorders. Although many efforts had been made in establishing models with statistical or machine learning algorithms, a comprehensive database resource is still missing. Since the records of experimental-validated protein mis-localization events spread across many literatures, a collection of all these reports in a unique website is demanded. In this paper, we created the dbMisLoc database by manually curating conditional protein mis-localization events from various literatures. The dbMisLoc database records the protein localizations, mis-localizations, conditions for mis-localization, and the original reports. The dbMisLoc database allows the users to intuitively view, search, visualize and download protein mis-localization records. The dbMisLoc database integrates a BLAST search engine, which can search mis-localized proteins that are similar to user queries. The dbMisLoc database can be accessed directly through ( https://dbml.pufengdu.org ). The source code of dbMisLoc database is available from the GitHub repository ( https://github.com/quinlanW/dbMisLoc ) for free. Users can host their own mirrors of dbMisLoc database on their own servers. dbMisLoc is database for manually curated protein mis-localization events. It contains mis-localization events in 14 categories of conditions such as diseases, drug treatments and environmental stresses.


Assuntos
Proteínas , Software , Proteínas/metabolismo , Algoritmos , Bases de Dados Factuais , Aprendizado de Máquina
12.
Acta Paediatr ; 112(2): 305-310, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36239417

RESUMO

AIM: The aim of this study is to explore the correlation between hepatocyte proliferation and hepatitis B virus (HBV) clearance in young children with chronic HBV infection. METHODS: We collected liver biopsy samples and clinical data corresponding to paediatric patients with chronic HBV infection. Ki-67 expression in liver tissues was evaluated by immunohistochemical staining. RESULTS: Eighteen patients were included and were divided into two groups based on different antiviral outcomes. Group I achieved hepatitis B surface antigen (HBsAg) loss within 48 weeks. Group II did not develop seroconversion from hepatitis B e (HBe) antigen to anti-HBe after 48 weeks. There were 10 patients in Group I and 8 in Group II, respectively. Demographical data and baseline virological and biochemical characteristics in serum across Group I and Group II were not statistically different. Histologically, mean Ki-67 expression index in Group I was 15%, while the mean index in Group II was 5%. There was a significant difference between the two groups (p < 0.01). CONCLUSION: High Ki-67 expression can contribute to viral clearance in young children with chronic HBV infection. This is the first confirmation of the association between hepatocyte proliferation and HBV clearance in vivo and has implications for novel therapeutic strategies against hepatitis B.


Assuntos
Hepatite B Crônica , Hepatite B , Criança , Pré-Escolar , Humanos , Antivirais/uso terapêutico , DNA Viral/uso terapêutico , Antígenos E da Hepatite B , Antígenos de Superfície da Hepatite B/uso terapêutico , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatócitos , Antígeno Ki-67 , Proliferação de Células
13.
Sleep ; 46(3)2023 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-36462192

RESUMO

STUDY OBJECTIVES: To investigate the relationship between sleep transition dynamics and stage-specific functional connectivity (FC) of the anterior cingulate cortex (ACC) in patients with insomnia disorder (ID). METHODS: Simultaneous electroencephalography-functional magnetic resonance imaging (EEG-fMRI) data from 37 patients with ID and 30 well-matched healthy controls (HCs) were recorded during wakefulness and different sleep stages and subsequently analyzed. A Markov chain model was used to estimate the transition probability between each stage. The FC between the ACC (set as the seed) and voxels across the whole brain was calculated. A linear mixed effect model was used to determine the group-by-stage interaction of the seed-based connectivity. The correlation between the sleep-stage transition probability and the ACC-based connectivity was explored. RESULTS: Patients with ID exhibited a higher likelihood of transitioning from N2 to wakefulness than HCs. A significant group-by-stage interaction of connectivity with the bilateral ACC was observed in the cerebellar, subcortical, and cortical regions. Moreover, a significant positive correlation was found in patients with ID between the transition probability from N2 to wakefulness and the FC of the ACC with the anterior cerebellum in N2 (r = 0.48). CONCLUSIONS: This exploratory analysis indicates that enhanced FC between the ACC and cerebellum represents a potential neural pathway underlying the greater likelihood of patients with ID waking during N2 sleep. These findings contribute to an emerging framework that reveals the link between sleep maintenance difficulty and ACC function, further highlighting the possibility that N2 sleep is a therapeutic target for meaningfully reducing sleep disruption.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Encéfalo , Sono , Fases do Sono , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos
14.
Aging (Albany NY) ; 14(23): 9715-9729, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36470668

RESUMO

To develop an individualized gene-based risk score to predict the prognosis of muscle-invasive bladder cancer (MIBC) patients who received GC regimens. We downloaded transcriptome profiling data and clinical information from the Cancer Genome Atlas (TCGA) database. We identified 1854 survival-associated genes and then constructed the risk score based on six special genes selected from the survival-associated genes. We divided patients into high-risk and low-risk groups according to the median risk score. High-risk patients have significantly poorer overall survival than low-risk patients (log-rank test chi-square = 38.08, p = 7e-10, C-index = 0.785, se = 0.032). The risk score was evaluated by Kaplan-Meier survival curve, time-dependent ROC curves, and C-index. Multivariate Cox regression and nomogram suggested that the risk score was an independent prognostic indicator. Gene set enrichment analysis indicated that the survival-associated genes were significantly enriched in immune-related terms. Among six special genes, CHPF2, TRAV26-2, and BTF3P12 were found to be immune-related genes. In conclusion, our risk score provided an indicator to predict the prognosis of MIBC patients who received GC regimens and potential immunotherapeutic targets for MIBC.


Assuntos
Cisplatino , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/uso terapêutico , Gencitabina , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Fatores de Risco , Prognóstico , Músculos
15.
Luminescence ; 37(9): 1524-1531, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35815832

RESUMO

In this work, a highly efficient electrochemiluminescence (ECL) biosensor was developed based on the nanosponge-hydrogel system for uric acid (UA) detection. First, the nanosponge consisted of polylactic acid glycolic acid (PLGA) nanoparticles immobilized with MoS2 quantum dots (QDs) and urate oxidase (UAO). The marked loading capability of PLGA nanoparticles enables loading many biomolecules and QDs for the specific recognition of UA. Urate oxidase on the nanosponge can catalyze UA to generate H2 O2 in situ, which further triggers the ECL signal for the MoS2 QDs. Furthermore, the biocompatible acrylamide-based hydrogel not only effectively retained the functionalities of the chimeric nanosponge-hydrogel, but also provided structural integrity and engineering flexibility on the electrode for ECL sensing applications. In addition, there were many ester groups and amide bonds in the nanosponge-hydrogel structure. Therefore, many electron can be excited in the ECL process due to the large number of lone electron pairs on oxygen and nitrogen atoms. This resulted in a seven-fold ECL enhancement of the MoS2 QDs. Finally, the nanosponge-hydrogel structure-based ECL biosensor was successfully used in real clinical serum assays. This showed a good analytical performance for UA detection (100-500 µmol/L) with a limit of detection of 20 µmol/L.


Assuntos
Técnicas Biossensoriais , Pontos Quânticos , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Hidrogéis , Medições Luminescentes/métodos , Molibdênio/química , Pontos Quânticos/química , Urato Oxidase , Ácido Úrico
16.
ACS Appl Mater Interfaces ; 14(28): 32166-32175, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35802864

RESUMO

Achieving high thermoelectric properties of CaMnO3 ceramics is significant for its applications at high temperature. Herein, Ca0.87Ag0.1Dy0.03MnO3 ceramics with plate-like template seeds additives were prepared by using a solid-state reaction method. The multiscale defects, including grain boundaries, oxygen defects, and Ag nanoprecipitations, which were regulated by the different sintering atmospheres, were beneficial for electron transport and phonon scattering. The grain boundaries as coherent interfaces could act as an alternative phonon scattering source. Oxygen vacancies coupled with Ag nanoprecipitations were verified by geometric phase analysis and annular bright-field analysis. The decrement in oxygen vacancies concentration strongly depended on the enriched oxygen environment, which could reduce electrical resistivities. Compared to the sample sintered at Ar atmosphere, a 17.5 times increment in power factor and a 20.1% reduction of the total thermal conductivity were obtained for the sample sintered at O2 atmosphere. As a result, the maximum ZT value of 0.22 was obtained at 500 °C. It is an effective way for improving the thermoelectric performance of oxide-based thermoelectric materials.

17.
Neuroimage Clin ; 35: 103111, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35863180

RESUMO

BACKGROUND: Positron emission tomography - computed tomography (PET-CT) research has shown that sleep discrepancy recorded by self-report and polysomnography (PSG) may be related to the altered metabolic rate of the anterior insula (aINS) during non-rapid eye movement (NREM) sleep in patients with insomnia disorder. We aim to explore the functional connectivity of aINS across wake and NREM sleep in the patients and to reveal the association between aINS connectivity and sleep discrepancy. METHODS: Patients with insomnia disorder (n = 33) and healthy controls (n = 31) underwent simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) during nighttime sleep, and aINS-based connectivity was calculated across wake and NREM sleep. A linear mixed-effects model was used to assess the main effect of group and group-by-stage (wake, NREM stages 1-3) interaction effect on aINS connectivity. Similar mixed models were used to assess the potential correlation between aINS connectivity and the sleep misperception index (MI). RESULTS: A significant group-by-stage interaction effect on aINS-based connectivity was observed in the bilateral frontal gyrus, right inferior temporal gyrus, bilateral middle occipital gyrus and right postcentral gyrus (p < 0.05, corrected). There was also a significant group-by-MI interaction effect on aINS connectivity with the putamen and thalamus during wakefulness (p < 0.05 corrected); MI was significantly associated with aINS-putamen/thalamus connectivity in the control group, whereas the association was weak or even nonsignificant in the patient group. There was no significant main effect of group. CONCLUSION: The waking activity of a neural pathway containing the aINS, putamen, and thalamus may underlie sleep perception, potentially providing important perspectives to reveal complex mechanisms of sleep discrepancy between self-report and PSG.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Eletroencefalografia/métodos , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sono , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem
18.
Appl Bionics Biomech ; 2022: 2801229, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35510044

RESUMO

Purpose: The reconstruction of a tendon insertion on metal prostheses is a challenge in orthopedics. Of the available metal prostheses, porous metal prostheses have been shown to have better biocompatibility for tissue integration. Therefore, this study is aimed at identifying an appropriate porous structure for the reconstruction of a tendon insertion on metal prostheses. Methods: Ti6Al4V specimens with a diamond-like porous structure with triply periodic minimal surface pore sizes of 300, 500, and 700 µm and a porosity of 58% (designated Ti300, Ti500, and Ti700, respectively) were manufactured by selective laser melting and were characterized with micro-CT and scanning electron microscopy for their porosity, pore size, and surface topography. The porous specimens were implanted into the patellar tendon of rabbits. Tendon integration was evaluated after implantation into the tendon at 4, 8, and 12 weeks by histology, and the fixation strength was evaluated with a pull-out test at week 12. Results: The average pore sizes of the Ti300, Ti500, and Ti700 implants were 261, 480, and 668 µm, respectively. The Ti500 and Ti700 implants demonstrated better tissue growth than the Ti300 implant at weeks 4, 8, and 12. At week 12, the histological score of the Ti500 implant was 13.67 ± 0.58, and it had an area percentage of type I collagen of 63.90% ± 3.41%; both of these results were significantly higher than those for the Ti300 and Ti700 implants. The pull-out load at week 12 was also the highest in the Ti500 group. Conclusion: Ti6Al4V implants with a diamond-like porous structure with triply periodic minimal surface pore size of 500 µm are suitable for tendon integration.

19.
J Am Chem Soc ; 144(5): 2095-2100, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35099946

RESUMO

The hitherto elusive benzo[c]anthanthrenyl radical derivatives composed of seven fused six-membered rings are synthesized and isolated in the crystalline form, representing a laterally π-extended doublet open-shell graphene fragment compared to the phenalenyl and olympicenyl radical structures. X-ray crystallographic analysis revealed one-dimensional chain stacking with relatively close intermolecular contacts, which is an important precondition for achieving single-component conductors. The magnetic, optical, and redox properties are investigated in the solution phase. In combination with the good stability, such open-shell molecular systems have potentials as functional electronic materials.

20.
Mitochondrial DNA B Resour ; 6(12): 3364-3366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34796264

RESUMO

Astragalus scaberrimus Bunge 1833 is a widespread perennial herb in northern China. The plant has white flowers and white hairs on the leaves and stems. To determine the chloroplast genome, total DNA was extracted from a sample and sequenced on the Illumina HiSeq4000 platform. After sequencing, the reads of chloroplast DNA were assembled and annotated via NOVOPlasty and PGA respectively. The chloroplast genome of this plant has a circular form with a length of 123,492 bp, a 34% GC content and IR loss. After annotation, a total of 113 genes were predicted for this cp genome, comprising 79 encoded proteins, 4 rRNAs and 30 tRNAs. The evolutionary history indicates that A. scaberrimus was grouped within Astragalus and formed a clade with Astragalus laxmannii with a 100% BS support value. The complete chloroplast genome can serve as a reference for future studies on molecular biology, evolution, population genetics, taxonomy and resource protection.

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