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1.
Artif Organs ; 48(1): 37-49, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37846614

RESUMEN

BACKGROUND: The artificial anal sphincter (AAS) system has gained significant attention as a solution for treating fecal incontinence (FI). It relies on transcutaneous energy transfer (TET) as its primary energy source. However, changes in posture or biological tissue can cause misalignment of the coil, resulting in unstable power reception. Inadequate power affects charging efficiency, while excessive power leads to excessive heating at the receiver side. Consequently, achieving safe and constant voltage charging for the AAS becomes a complex challenge. METHODS: To maintain a consistent charging voltage and overcome the issue of variations in load and coil coupling strength, this article proposes a wireless charging control system that utilizes an LCC-S-type resonant network and phase shift to adjust the transmitting voltage based on feedback charging voltage in real time. In particular, the PI controller and neural network are introduced to change the phase-shift angle swiftly. The dynamic performance is then evaluated under different misalignments and presented with comparative results. RESULTS: The results indicate that the multilayer perceptron control system outperforms the PI. Under the complex misalignment disturbance, the average error of receiver side load voltage is only 0.007 V, with an average settling time of 960 ms. Additionally, the average temperature at the receiver side is 40.4°C. CONCLUSION: The experiments demonstrate that the proposed system effectively addresses the misalignment issue in TET during the charging, ensuring constant voltage charging at the receiver side and thermal safety.


Asunto(s)
Órganos Artificiales , Esfínter Urinario Artificial , Canal Anal/cirugía , Transferencia de Energía , Redes Neurales de la Computación
2.
Artif Organs ; 47(11): 1710-1719, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37680050

RESUMEN

BACKGROUND: Artificial anal sphincter is an implantable medical device for treating fecal incontinence. Reasonable simulation facilitates the advancement of research and reduces experiments on biological tissue. However, the device's clamping motion and sensor interaction with the intestine in the simulation still require further exploration. This article presents a simulation of the artificial anal sphincter's clamping and sensing and its interaction with the intestinal environment using the Simulation Open Framework Architecture (SOFA). METHODS: Firstly, the proposed simulation algorithm and its principles in SOFA are analyzed. Secondly, the clamping motion and sensor system of the artificial anal sphincter are simulated. Thirdly, a finite element model of intestine is established based on the properties of intestinal soft tissue. Finally, the in vitro experiments are performed. RESULTS: The simulation results indicate that the sensor system of the artificial anal sphincter has good sensing performance during the clamping motion and fecal accumulation process. Experiments have shown that optimal sensory capabilities can be achieved as the posture of the artificial anal sphincter with a roll angle between 20° and 40°. The comparison demonstrates a mean absolute error of 10%-20% between simulation and in vitro experimental results for sensor forces, which verifies the effectiveness of the simulation. CONCLUSION: The proposed novel simulation achieves a more comprehensive interaction between the artificial anal sphincter motion and intestinal environment. This study may provide more effective simulation data for guidance in improving the performance of sensor perception of artificial anal sphincter for further research.


Asunto(s)
Órganos Artificiales , Incontinencia Fecal , Esfínter Urinario Artificial , Humanos , Canal Anal/cirugía , Prótesis e Implantes , Incontinencia Fecal/cirugía
3.
J Environ Manage ; 347: 119059, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37769469

RESUMEN

Global ornamental horticulture is a major pathway for plant invasions, while urban parks are key areas for introducing non-native ornamental plants. To react appropriately to the challenges (e.g., biological invasion issues) and opportunities (e.g., urban ecosystem services) of herbaceous ornamentals in urban parks, we conducted a comprehensive invasive risk assessment in 363 urban parks in Chongqing, a subtropical city in China. The results found more than 1/3 of the 119 non-native species recorded in urban parks had a high invasion risk, and more than five species had potential invasion risk in 96.29% of the study area, indicating herbaceous ornamentals in urban parks are potentially a pool of invasive species that deserves attention. Moreover, humans have chosen herbaceous ornamentals with more aesthetic characteristics in urban parks, where exotic species were more prominent than native species in floral traits, such as more conspicuous flowers and longer flowering periods. The findings can inform urban plant management, provide an integrated approach to assessing herbaceous ornamentals' invasion risk, and offer insights into understanding the filtering effects of human aesthetic preferences.


Asunto(s)
Ecosistema , Parques Recreativos , Humanos , Plantas , Especies Introducidas , Reproducción
4.
Zoolog Sci ; 31(6): 348-52, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24882094

RESUMEN

In many species, nestling demands vary continuously during early development and both parents have different parental care strategies at each nestling age. Sexual conflict arises when each parent expects its partner investing more in parental care. It is largely unknown how the two parents respond to the dynamics of nestling demands and resolve the sexual conflict during nestling period, especially on Qinghai-Tibetan Plateau. To address this question, we monitored parental care behaviors of horned larks (Eremophila alpestris) using video-recording systems. We found that male horned larks invested less in parental care, but had a larger body size than females, which is consistent with the parental investment hypothesis. Only the female brooded nestlings, but both parents contributed to feeding efforts. Feeding rates of males and females were negatively correlated, indicating that they used evolutionarily stable strategies. Strategies of parental care via nestling age were sex-specific. Females continuously adjusted care behaviors to follow the dynamics of nestling demands as nestling age increased, such as decreasing brood attentiveness and increasing feeding rate. By contrast, male feeding rate showed no significant correlation with nestling age, but increased with the synchrony feeding rate. We suggest the synchrony feeding behavior may act as a control measure for females to promote and assess the males' contribution. We consider low mating opportunities drive males to act as assistants for females, and correspondingly cause males to pay less attention to nestling demands than females.


Asunto(s)
Conducta Animal/fisiología , Responsabilidad Parental , Passeriformes/fisiología , Animales , Femenino , Masculino , Factores Sexuales
5.
MycoKeys ; 105: 49-95, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38708027

RESUMEN

The first occurrence of Marasmiellomycena and Pulverulina in the Chinese mycobiota are reported, M.tomentosa and P.flavoalba, two new species and M.albodescendens, a new combination, revealed by phylogenetic analyses and morphological study. These newly-recorded genera, Marasmiellomycena, which can be distinguished by their agaricoid basidiomata, dark-coloured stipe, sarcodimitic tramal structure, stipitipellis with yellow to yellowish-brown pigments and yellow-pigmented thick-walled caulocystidia and Pulverulina, which differs from other genera of Porotheleaceae by its pruinose stipe, decurrent lamellae, inamyloid basidiospores and absence of hymenial cystidia. We also formally describe three other new species of Porotheleaceae collected from Chinese temperate to subtropical zones of Fujian and Zhejiang Provinces: Clitocybulafuscostriata, Gerronemabrunneosquamulosum and Leucoinocybesubglobispora. Furthermore, we include the results of a phylogenetic analysis of Porotheleaceae, based on a multi-locus (ITS, nrLSU and rpb2) dataset. According to this analysis, Chrysomycena, Clitocybula, Delicatula, Hydropodia, Hydropus, Leucoinocybe, Marasmiellomycena, Megacollybia, Pulverulina, Trogia and Vizzinia are monophyletic. However, Gerronema is identified as polyphyletic and, additionally, Porotheleum does not form a monophyletic group either because Porotheleumparvulum and Porotheleumalbidum are "unassigned" in phylogenetic analysis. The results of our phylogenetic analyses, coupled with morphological observations, confirm recognition of these new taxa. Morphological descriptions, photographs, line drawings and comparisons with closely-related taxa are presented for the new species. A key to the 22 species belonging to nine genera of Porotheleaceae in China is also provided.

6.
Zhonghua Liu Xing Bing Xue Za Zhi ; 36(8): 889-95, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26714550

RESUMEN

OBJECTIVE: To analyze the associations between air pollution and adverse health outcomes on respiratory diseases and to estimate the short-term effects of air pollutions [Particulate matter with particle size below 10 microns (PM(10)), PM(10) particulate matter with particle size below 2.5 microns (PM(2.5)), nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3)] on respiratory mortality in China. METHODS: Data related to the epidemiological studies on the associations between air pollution and adverse health outcomes of respiratory diseases that published from 1989 through 2014 in China, were collected by systematically searching databases of PubMed, SpringerLink, Embase, Medline, CNKI, CBM and VIP in different provinces of China. Short-term effects between (PM(10), PM(2.5), NO2, SO2, O3) and respiratory mortality were analyzed by Meta-analysis method, and estimations were pooled by random or fixed effect models, using the Stata 12.0 software. RESULTS: A total of 157 papers related to the associations between air pollution and adverse health outcomes of respiratory diseases in China were published, which covered 79.4% of all the provinces in China. Results from the Meta-analysis showed that a 10 µg/m³ increase in PM10, PM(2.5), NO2, SO2, and O3was associated with mortality rates as 0.50% (95% CI: 0-0.90%), 0.50% (95% CI: 0.30%-0.70%), 1.39% (95% CI: 0.90%-1.78%), 1.00% (95% CI: 0.40%-1.59%) and 0.10% (95% CI: -1.21%-1.39%) in respiratory tracts, respectively. No publication bias was found among these studies. CONCLUSION: There seemed positive associations existed between PM(10)/PM(2.5)/NO2/SO2and respiratory mortality in China that the relationship called for further attention on air pollution and adverse health outcomes of the respiratory diseases.


Asunto(s)
Contaminación del Aire/efectos adversos , Enfermedades Respiratorias/epidemiología , Enfermedades Respiratorias/mortalidad , Contaminantes Atmosféricos , China/epidemiología , Humanos , Modelos Teóricos , Dióxido de Nitrógeno , Ozono , Material Particulado , Dióxido de Azufre
7.
Acta Biomater ; 25: 194-204, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26193000

RESUMEN

Small interfering RNAs (siRNAs) are extensively studied due to their promising potential as therapeutic agents for a wide variety of diseases, including cancer. However, efficient delivery of siRNAs to target cells and tissues is problematic due to a lack of suitable delivery vehicles. In this work, we developed a layer-by-layer assembled chitosan-gold nanorods (Chit-Au NRs) siRNA delivery system to overcome biological barriers upon systemic injection. This platform was able to protect siRNAs form degradation upon exposure to ribonuclease (RNase) or serum. Confocal and intravital microscopy reveals that Chit-Au NRs/siRNAs are successfully delivered into target cells and tissue, and can efficiently escape from endosomal/lysosomal structures. Furthermore, Chit-Au NRs/siRNA were found to accumulate in high levels in tumor tissue. The delivery system was able to inhibit the oncogene expression (pyruvate kinase isozymeM2, PKM2) in MDA-MB-231 triple negative breast cancer cells, resulting in suppression of cell proliferation and migration. Moreover, the anticancer efficacy was further enhanced through NR-mediated photothermal ablation. In conclusion, the synergistic therapeutic properties of Chit-Au NRs/siRNA enable effective suppression of cancer growth. STATEMENT OF SIGNIFICANCE: Small interfering RNA (siRNA) therapy has promising therapeutic applications, since the expression of any protein can be suppressed. However the successful implementation of siRNA has been challenging, due to rapid degradation, poor intracellular uptake and insufficient endosomal escape. Here, we have developed a gold nanorod/chitosan-based delivery vehicle for siRNA therapy. This platform successfully overcomes the afore-mentioned challenges and can simultaneously be used for photothermal therapy, due to the optical properties of gold nanorods. We show that the anticancer activity is dramatically improved by combining thermal therapy with gene silencing. Furthermore, the Au NRs carrier shows high accumulation in tumor tissue and high transfection efficiency. This manuscript has been reviewed and approved by all co-authors. The research has not been disclosed or published and is not under consideration for publication elsewhere. We would appreciate if the manuscript could be reviewed and considered for publication in Acta BIOMATERIALIA.


Asunto(s)
Quitosano/química , Silenciador del Gen , Oro/química , Hipertermia Inducida , Nanotubos/química , Fototerapia , Neoplasias de la Mama Triple Negativas/terapia , Línea Celular Tumoral , Movimiento Celular , Supervivencia Celular , Endocitosis , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Transferencia de Gen , Humanos , Espacio Intracelular/metabolismo , Nanotubos/ultraestructura , Distribución Tisular , Neoplasias de la Mama Triple Negativas/patología
8.
Dongwuxue Yanjiu ; 33(2): 127-32, 2012 Apr.
Artículo en Zh | MEDLINE | ID: mdl-22467386

RESUMEN

Phrynocephalus przewalskii is one kind of lizards inhabiting inclusively in the desert that has controversial viewpoints on its phylogeny. Based on mitochondrial ND2 gene of 119 samples from 12 geographic populations, we analyzed the effects of environmental factors on the variation of genetic diversity, as well as its relationship to P. versicolor. The results showed that these populations clustered into three major lineages, with P. versicolor embedded within one lineage. The twelve populations had great genetic diversity variation, which was tightly linked with local altitude, annual precipitation, and variation of annual precipitation. High latitudes, increased annual precipitation and great variation in annual precipitations may all have resulted in the decrease of genetic diversity. It thus assumed that altitude can change the genetic diversity of different geographic populations of P. przewalskii resulting from the effects of different local annual precipitation.


Asunto(s)
Lagartos/genética , Animales , Variación Genética , Lagartos/clasificación , Filogenia
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