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1.
Ecotoxicol Environ Saf ; 284: 116889, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39186840

RESUMEN

Infertility has become one of the most common chronic diseases among reproductive- aged individuals, and male factors account for about 50 %. Zinc is a trace element that is essential for sperm quality and male reproductive system. Although several current studies with small sample sizes have investigated this relationship, the conclusions have been still controversial. Here, using a large population sample involved 25,915 participants from Changzhou Maternity and Child Health Care Hospital, we revealed an inverted "U"-shaped trend between seminal plasma zinc concentrations and sperm motility PR/PR + NP (PR, progressive motility; NP, non-progressive motility). The results showed that the highest values of sperm PR/PR + NP observed in the group with intermediate concentrations of zinc (Group 2, 0.25-2.11 mmol/L). The mean values were 43.17 ± 19.03 % and 56.64 ± 20.28 %, respectively. And the lowest values came out in the highest zinc levels group (Group 4, > 3.04 mmol/L). In vitro cell experiments also showed that zinc caused dose-dependent cytotoxicity for GC-2 cells at a threshold value. Furthermore, RNA-seq analysis demonstrated that high concentrations of zinc exerted toxic effects on GC-2 cells through immune injury. Taken together, our findings suggested that moderate amounts of zinc are crucial for human reproduction and excessive concentrations may have adverse effects on male fertility.


Asunto(s)
Análisis de Semen , Semen , Motilidad Espermática , Zinc , Masculino , Humanos , Zinc/toxicidad , Motilidad Espermática/efectos de los fármacos , Semen/efectos de los fármacos , Adulto , China , Espermatozoides/efectos de los fármacos
2.
Dement Geriatr Cogn Disord ; 52(4): 240-248, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37433284

RESUMEN

INTRODUCTION: Alzheimer's disease (AD) is the most prevalent type of dementia and can cause abnormal cognitive function and progressive loss of essential life skills. Early screening is thus necessary for the prevention and intervention of AD. Speech dysfunction is an early onset symptom of AD patients. Recent studies have demonstrated the promise of automated acoustic assessment using acoustic or linguistic features extracted from speech. However, most previous studies have relied on manual transcription of text to extract linguistic features, which weakens the efficiency of automated assessment. The present study thus investigates the effectiveness of automatic speech recognition (ASR) in building an end-to-end automated speech analysis model for AD detection. METHODS: We implemented three publicly available ASR engines and compared the classification performance using the ADReSS-IS2020 dataset. Besides, the SHapley Additive exPlanations algorithm was then used to identify critical features that contributed most to model performance. RESULTS: Three automatic transcription tools obtained mean word error rate texts of 32%, 43%, and 40%, respectively. These automated texts achieved similar or even better results than manual texts in model performance for detecting dementia, achieving classification accuracies of 89.58%, 83.33%, and 81.25%, respectively. CONCLUSION: Our best model, using ensemble learning, is comparable to the state-of-the-art manual transcription-based methods, suggesting the possibility of an end-to-end medical assistance system for AD detection with ASR engines. Moreover, the critical linguistic features might provide insight into further studies on the mechanism of AD.


Asunto(s)
Enfermedad de Alzheimer , Percepción del Habla , Humanos , Enfermedad de Alzheimer/psicología , Lingüística , Habla , Cognición
3.
Macromol Rapid Commun ; 44(20): e2300304, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37585219

RESUMEN

Understanding how small molecules penetrate and contaminate polymer films is of vital importance for developing protective coatings for a wide range of applications. To this end, rhodamine B fluorescent dye is visualized diffusing through polystyrene-polydimethylsiloxane block copolymer (BCP) coatings using confocal microscopy. The intensity of dye inside the coatings grows and decays non-monotonically, which is likely due to a combination of dye molecule transport occurring concurrently in different directions. An empirical fitting equation allows for comparing the contamination rates between copolymers, demonstrating that dye penetration is related to the chemical makeup and configuration of the BCPs. This work shows that confocal microscopy can be a useful tool to visualize the transport of a fluorophore in space and time through a coating.


Asunto(s)
Colorantes Fluorescentes , Polímeros , Polímeros/química , Colorantes Fluorescentes/química , Poliestirenos
4.
Sensors (Basel) ; 16(9)2016 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-27598163

RESUMEN

Four custom fiber Bragg grating (FBG)-based sensors are developed to monitor an artificial landslide located in Nanjing, China. The sensors are composed of a rod and two FBGs. Based on the strength of the rods, two sensors are referred to as "hard sensors" (Sensor 1 and Sensor 2), the other two are referred to as "soft sensors" (Sensor 3 and Sensor 4). The two FBGs are fixed on each sensor rod at distances of 50 cm and 100 cm from the top of the rod (an upper FBG and a lower FBG). In the experiment presented in this paper, the sensors are installed on a slope on which an artificial landslide is generated through both machine-based and manual excavation. The fiber sensing system consists of the four custom FBG-based sensors, optical fiber, a static fiber grating demodulation instrument (SM125), and a PC with the necessary software. Experimental data was collected in the presence of an artificial landslide, and the results show that the lower FBGs are more sensitive than the upper FBGs for all four of the custom sensors. It was also found that Sensor 2 and Sensor 4 are more capable of monitoring small-scale landslides than Sensor 1 and Sensor 3, and this is mainly due to their placement location with respect to the landslide. The stronger rods used in the hard sensors make them more adaptable to the harsh environments of large landslides. Thus, hard sensors should be fixed near the landslide, while soft sensors should be placed farther away from the landslide. In addition, a clear tendency of strain variation can be detected by the soft sensors, which can be used to predict landslides and raise a hazard alarm.

5.
ACS Appl Mater Interfaces ; 16(15): 19594-19604, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38588386

RESUMEN

Polydimethylsiloxane (PDMS) has been widely used as a surface coating material, which has been reported to possess dynamic omniphobicity to a wide range of both polar and nonpolar solvents due to its high segmental flexibility and mobility. However, such high flexibility and mobility also enable penetration of small molecules into PDMS coatings, which alter the chemical and physical properties of the coating layers. To improve the anti-penetration properties of PDMS, a series of fluorinated alkyl segments are grafted to a diblock copolymer of polystyrene-block-poly(vinyl methyl siloxane) (PS-b-PVMS) using thiol-ene click reactions. This article reports the chemical characterization of these model fluorosilicone block copolymers and uses fluorescence measurements to investigate the dye penetration characteristics of polymer thin films. The introduction of longer fluorinated alkyl chains can gradually increase the anti-penetration properties as the time to reach the maximum fluorescence intensity (tpeak) gradually increases from 11 s of PS-b-PVMS to more than 1000 s of PS-b-P(n-C6F13-VMS). The improvement of anti-penetration properties is attributed to stronger inter-/intrachain interactions, phase segregation of ordered fluorinated side chains, and enhanced hydrophobicity caused by the grafting of fluorinated alkyl chains.

6.
Artículo en Inglés | MEDLINE | ID: mdl-36430002

RESUMEN

Despite the significance of pro-environmental behavior (PEB) in the workplace, most of the existing studies have neglected its negative work outcomes. Drawing upon moral licensing theory and cognitive dissonance theory, we construct a conceptual model of the influence mechanism of employees' PEB (i.e., public-sphere PEB, private-sphere PEB) on workplace deviance through psychological entitlement, and the moderating effect of rationalization of workplace deviance on the relationship between psychological entitlement and workplace deviance. Using two-stage survey data from 216 employees in China, we performed hierarchical regression analysis and structural equation modeling method to test our hypotheses. Our findings reveal that public-sphere PEB positively affects psychological entitlement, while private-sphere PEB negatively affects psychological entitlement. Psychological entitlement further positively affects workplace deviance. In addition, rationalization of workplace deviance strengthens the positive impact of psychological entitlement on workplace deviance. This study offers novel insights into the dark side of PEB literature by exploring the PEB-workplace deviance relationship. This study also contributes to managerial implications of how PEB leads to workplace deviance and how to address this issue.


Asunto(s)
Conducta Social , Lugar de Trabajo , Humanos , Lugar de Trabajo/psicología , Creatividad , Encuestas y Cuestionarios , China
7.
Brain Sci ; 12(12)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36552095

RESUMEN

OBJECTIVE: The virtual reality (VR)-based path integration task shows substantial promise in predicting dementia risk. However, the reliability and validity in healthy populations need further exploration. The present study investigates the relationship between task indicators and brain structures in a healthy population using a VR-based navigation task, particularly the entorhinal cortex (EC) and hippocampus. METHODS: Sixty healthy adults were randomly recruited to perform a VR-based path integration task, the digit span task (DST), and an MRI scan. The indicators of the VR-based path integration task were calculated, including the absolute distance error (ADE), degree of angle deviation (DAD), degree of path deviation (DPD), and return time (Time). The reliability of the above indicators was then estimated using the split-half method and Cronbach's alpha. Correlation and regression analyses were then performed to examine the associations between these indicators and age, general cognitive ability (DST), and brain structural measures. RESULTS: ADE, DAD, and DPD showed reasonable split-half reliability estimates (0.84, 0.81, and 0.72) and nice Cronbach's alpha estimates (0.90, 0.86, and 0.96). All indicators correlated with age and DST. ADE and DAD were sensitive predictors of hippocampal volume, and return time was a predictor of EC thickness. CONCLUSION: Our findings demonstrate that the VR-based path integration task exhibits good reliability and validity in the healthy population. The task indicators are age-sensitive, can capture working memory capacity, and are closely related to the integrity of individual EC and hippocampal structures.

8.
Int J Comput Assist Radiol Surg ; 17(10): 1751-1764, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35639202

RESUMEN

PURPOSE: Due to respiratory motion, precise tracking of lung nodule movement is a persistent challenge for guiding percutaneous lung biopsy during image-guided intervention. We developed an automated image-guided system incorporating effective and robust tracking algorithms to address this challenge. Accurate lung motion prediction and personalized image-guided intervention are the key technological contributions of this work. METHODS: A patient-specific respiratory motion model is developed to predict pulmonary movements of individual patients. It is based on the relation between the artificial 4D CT and corresponding positions tracked by position sensors attached on the chest using an electromagnetic (EM) tracking system. The 4D CT image of the thorax during breathing is calculated through deformable registration of two 3D CT scans acquired at inspiratory and expiratory breath-hold. The robustness and accuracy of the image-guided intervention system were assessed on a static thorax phantom under different clinical parametric combinations. RESULTS: Real 4D CT images of ten patients were used to evaluate the accuracy of the respiratory motion model. The mean error of the model in different breathing phases was 1.59 ± 0.66 mm. Using a static thorax phantom, we achieved an average targeting accuracy of 3.18 ± 1.2 mm across 50 independent tests with different intervention parameters. The positive results demonstrate the robustness and accuracy of our system for personalized lung cancer intervention. CONCLUSIONS: The proposed system integrates a patient-specific respiratory motion compensation model to reduce the effect of respiratory motion during percutaneous lung biopsy and help interventional radiologists target the lesion efficiently. Our preclinical studies indicate that the image-guided system has the ability to accurately predict and track lung nodules of individual patients and has the potential for use in the diagnosis and treatment of early stage lung cancer.


Asunto(s)
Tomografía Computarizada Cuatridimensional , Neoplasias Pulmonares , Algoritmos , Tomografía Computarizada Cuatridimensional/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Movimiento (Física) , Movimiento , Fantasmas de Imagen , Respiración
9.
Chem Commun (Camb) ; 55(63): 9387-9390, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31318363

RESUMEN

Creating stimuli-responsive materials with switchable solid-state luminescence remains a challenge. We report that the solvation of a novel organic fluorophore can be utilized to prepare such a material, which emits in the blue (442-446 nm) region when wet and in the green (497-503 nm) region when dry.

10.
Chem Commun (Camb) ; 54(82): 11578-11581, 2018 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-30260356

RESUMEN

Dicarboxylic acids are important chemicals in human metabolism and various industries. Differentiation between the isomers and members of a homologous series is a challenge, due to their similar properties. We show that a triazine-based fluorinated AIEgen can recognize dicarboxylic acids with selectivity based on the relative position of the two -COOH groups.

11.
Chem Commun (Camb) ; 53(72): 10022-10025, 2017 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-28836634

RESUMEN

Trigonal fluorinated pyrazoles assemble into porous molecular crystals and show solid-state fluorescence. However, in a DMF/H2O mixed solvent system, the triazine-centered compound displays aggregation-induced emission, while its benzene-based counterpart does not.

12.
Zhonghua Yi Xue Za Zhi ; 89(42): 2953-5, 2009 Nov 17.
Artículo en Zh | MEDLINE | ID: mdl-20137701
13.
ACS Appl Mater Interfaces ; 6(3): 2174-84, 2014 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-24443836

RESUMEN

In this paper, the hierarchical SnO2 nanostructures (HTNs) were prepared by a facile hydrothermal process. The prepared HTNs were characterized in detail by various analytical techniques that reveal the well-crystallinity with tetragonal rutile structure of SnO2 for the as-prepared material. By detailed experiments, interestingly, it was observed that the shapes and sizes of as-prepared HTNs could be tailored by varying the precursor concentration and reaction time. The synthesized HTNs were used as the efficient photocatalysts for the photocatalytic degradation of methylene blue (MB) under light illumination which showed almost complete degradation (∼99%) of MB dye in 20 min. The observed degradation for MB dye was higher than other commonly used dyes, i.e. methyl orange (MO; 96% in 50 min) and Rhodamine B (RhB; 97% in 40 min.). Further, the prepared HTNs were used as the effective gas sensing material to examine a series of volatile gases, such as ethanol, ammonia, benzene, acetone, toluene, methanol, diethyl ether, and methanol. By the detailed experiments, it was observed that the prepared HTNs exhibited tremendous gas sensing performance toward ethanol. Finally, because of the unique morphology and the fast ion and electron transfer characteristics, the prepared HTNs show excellent supercapacitor performances.

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