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1.
Iran J Public Health ; 53(5): 988-996, 2024 May.
Article in English | MEDLINE | ID: mdl-38912150

ABSTRACT

Background: We aimed to analyze the variability of the permanent trigeminal artery (PTA) and its relationship with cerebrovascular disease. Methods: To analyze the variability of the PTA and its relationship with cerebrovascular disease by using the terms "primitive trigeminal artery", "persistent primitive trigeminal artery", " persistent trigeminal artery variant", "PPTA", "PTAV", "carotid- basilar anastomoses", "carotid-vertebrobasilar anastomoses", "persisting embryonic vessels" were used as keywords, and the English-language literature related to PTA and cerebrovascular diseases published in PubMed, EMBAS, and Web of Science databases from 2000 to 2022 were searched by using "subject terms + free words". A meta-analysis of the collected data was performed using stata14.0 statistical software to assess the relationship between the immortal trigeminal artery and cerebrovascular-related diseases. Results: A total of 1908 relevant articles were initially retrieved for this study. Ten papers were initially screened according to the inclusion and exclusion criteria, while the literature was then read one by one to exclude duplicates, reviews, case reports, and conference abstracts, and six papers were finally included for meta-analysis. The six papers included in this paper were all cross-sectional studies with 39,355 subjects, of which 206 subjects had PTA, with a variation rate of approximately 0.52%, including 77 males and 129 females, 117 left-sided variants and 87 right-sided variants. In contrast, of the 206 subjects with a PTA, 52 had cerebrovascular disease, with an overall prevalence of approximately 25.24%. Conclusion: The PTA could influence the development of cerebrovascular disease.

2.
J Colloid Interface Sci ; 633: 207-217, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36446213

ABSTRACT

Pressure, analogous with temperature and composition, is other meaningful variant for tuning the structure-activity properties of layered materials. In-situ high-pressure electrical results discover that Vanadium based MXene (V2CTx MXene) conductivity is increased by one order of magnitude from ambient to 10.4 GPa, and then the conductivity is still fixated on meeting growth as pressure releasing. Increased carrier concentration due to denser compactness is the most important factor in improving sample conductivity. Furthermore, abundant of V2CTx samples after preloading different pressures are prepared by the mean of the double-anvil hydraulic press for the first time, and results of increased conductivity were reproduced at ambient conditions. The first-principles calculation of V2C (non-functional group), V2CF, V2CO, and V2COH explains for the lattice expansion by tracing emotion of different function groups upon decompression. Electrochemical results obtain that once forming V2CTx MXene anode rapidly quenched from 2.0 GPa in hydraulic press shows better performance, obviously weakening electric polarization and increasing Li-ion transport rate due to its proper interlaminar densification and improved conductivity. This work opens up a new, simple, and universal approach to develop MXene materials with superior electrical and electrochemical properties, as well as expanding the potential applications for energy storage.

3.
ACS Appl Mater Interfaces ; 14(40): 46056-46067, 2022 Oct 12.
Article in English | MEDLINE | ID: mdl-36170614

ABSTRACT

We studied the structure-function relationship of compressed Ti3C2Tx MXene using high-pressure in situ synchrotron radiation, impedance spectroscopy, Hall effect measurements, and first-principles calculations. With increasing pressure, the conductivity of Ti3C2Tx MXene increases along with its continued lattice shrinkage. A pressure range of 0.4-2.2 GPa exhibits a sharp decrease in resistance, which decreases by more than one order of magnitude from 3.3 × 104 to 1.4 × 103 Ω. A pressure range of 2.2-6.6 GPa exhibits a steady resistance with a slight decrease of 0.2%. As the pressure drops to atmospheric conditions, the resistance increases slightly to 4.2 × 103 Ω. This is accompanied by a transformation of the semiconductor into metal. An irreversible increase in conductivity is observed owing to an increase in the electron concentration and a decrease in the grain-boundary potential barrier. Furthermore, abundant Ti3C2Tx undergoing prepressure treatments (0.4, 2.0, and 4.0 GPa) was first prepared using a double-anvil hydraulic press. The recycled samples retain an accordion-like layered structure with slight lattice shrinkage while the voids between the sheets contract considerably, increasing the density. Correspondingly, electrochemical results show a pressure threshold of 2.0 GPa based on the rapid quenching from the hydraulic press. This weakens the electric polarization in redox reactions and increases the ionic transport rate for the formation of a Ti3C2Tx anode owing to pressure improving the conductivity and interlaminar densification. Our study shows a new, simple, and universal way to regulate various MXenes and also promotes the application of MXene-based materials in energy storage and related fields.

4.
IEEE Trans Image Process ; 30: 5252-5263, 2021.
Article in English | MEDLINE | ID: mdl-34033539

ABSTRACT

Auto-Encoder (AE)-based deep subspace clustering (DSC) methods have achieved impressive performance due to the powerful representation extracted using deep neural networks while prioritizing categorical separability. However, self-reconstruction loss of an AE ignores rich useful relation information and might lead to indiscriminative representation, which inevitably degrades the clustering performance. It is also challenging to learn high-level similarity without feeding semantic labels. Another unsolved problem facing DSC is the huge memory cost due to n×n similarity matrix, which is incurred by the self-expression layer between an encoder and decoder. To tackle these problems, we use pairwise similarity to weigh the reconstruction loss to capture local structure information, while a similarity is learned by the self-expression layer. Pseudo-graphs and pseudo-labels, which allow benefiting from uncertain knowledge acquired during network training, are further employed to supervise similarity learning. Joint learning and iterative training facilitate to obtain an overall optimal solution. Extensive experiments on benchmark datasets demonstrate the superiority of our approach. By combining with the k -nearest neighbors algorithm, we further show that our method can address the large-scale and out-of-sample problems. The source code of our method is available: https://github.com/sckangz/SelfsupervisedSC.

5.
Arch Med Res ; 45(3): 263-9, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24508287

ABSTRACT

BACKGROUND AND AIMS: Ghrelin is an endogenous ligand of the growth hormone (GH) secretagogue receptor and is closely associated with chronic heart failure (CHF). We undertook this study to investigate the relevance of ghrelin in CHF prognosis. METHODS: A total of 145 in-patients with CHF in NYHA class II, III or IV despite optimized therapy were prospectively included in the study, grouped according to NYHA class and compared with 55 healthy control subjects. Ghrelin and N-terminal pro-B-type natriuretic peptide (Nt pro-BNP) were measured in plasma by ELISA. Echocardiographic information was also measured, including left atrial dimension, left ventricular end-diastolic diameter, LV volume and left ventricular ejection fraction (LVEF). Patients were followed for 2 years or until major adverse cardiac events. RESULTS: Plasma ghrelin levels were significantly lower in patients with CHF than in control subjects (p = 0.014). In addition, plasma ghrelin levels differed significantly with the severity of CHF. Notably, survival analysis showed that high ghrelin levels were an indicator of a favorable prognosis for CHF. Our results also showed that ghrelin correlated inversely with plasma Nt pro-BNP levels (r = -0.562, p <0.001) and positively with LVEF (r = 0.620, p <0.001) in patients with CHF. Furthermore, multivariate analysis showed that ghrelin levels were independently associated with adverse cardiac events (hazard ratio: 0.72; 95% CI: 0.64-0.81, p = 0.03). CONCLUSIONS: Ghrelin is a new biomarker of CHF severity as well as a new prognostic predictor for patients with CHF. Future experimental and clinical studies are warranted to evaluate ghrelin as a novel prognostic tool and for its therapeutic potential in patients with CHF.


Subject(s)
Ghrelin/blood , Heart Failure/diagnosis , Adult , Aged , Biomarkers/blood , Case-Control Studies , Chronic Disease , Female , Heart Failure/blood , Heart Failure/diagnostic imaging , Heart Failure/physiopathology , Humans , Male , Middle Aged , Multivariate Analysis , Natriuretic Peptide, Brain/blood , Peptide Fragments/blood , Prognosis , Prospective Studies , Survival Analysis , Ultrasonography , Ventricular Function, Left
6.
Psychol Health Med ; 19(3): 365-73, 2014.
Article in English | MEDLINE | ID: mdl-23786566

ABSTRACT

OBJECTIVE: The aim of this study is to explore the relationship between psychological strains and depression and to further test the Strain Theory of Suicide and Mental Disorders. METHOD: Data for the current study were from a large psychological autopsy (PA) study in Chinese rural populations with a case-control design to investigate the environmental and other characteristics of rural young suicides and controls. Subjects (N = 1618) for the current study were the informants in the PA interviews. The center for epidemiologic studies depression scale was used to assess the respondents' depression level. Chi-square x², t test, t' test, and general linear regression model were used to analyse the data by SPSS software. RESULTS: Value strain and deprivation strain are positively correlated with the depression level for both men and women of the Chinese rural population. Religion is another strong risk factor for depression and marriage is not a protective factor for depression in this sample. CONCLUSIONS: The study verifies that there is strong correlation between the psychological strains and depression in Chinese rural populations. It is suggested that reducing psychological strains may be a possible approach to reduce the prevalence of depression so as to help bring down the suicide risk in rural China.


Subject(s)
Depression/psychology , Rural Population/statistics & numerical data , Stress, Psychological/psychology , Suicide/psychology , Adolescent , Adult , Case-Control Studies , China/epidemiology , Depression/epidemiology , Female , Humans , Male , Marriage/psychology , Middle Aged , Religion and Psychology , Risk , Stress, Psychological/epidemiology , Suicide/statistics & numerical data , Young Adult
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