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1.
Anal Chem ; 95(23): 8850-8858, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37260159

RESUMEN

Micromixers are a critical component in microfluidics. However, most 2D passive micromixers produce optimal mixing at a high flow rate range and 3D micromixers require mm-scale channels or a complex assembly that is unsuitable for microfluidic applications. Here, we reported a 3D PDMS micromixer based on the splitting-stretching-recombination (SSR) of streams to facilitate molecular diffusion, which can effectively and rapidly mix solutions with low Reynolds numbers (0.01-10). The fabrication of our micromixer is convenient with only two steps─two-photon polymerization (2PP) 3D printing and soft lithography, with high resolution, reproducibility, and ease for integration. We investigated the mixing performance of the micromixer by CFD simulations and experimental studies under a confocal microscope; the results confirmed its better performance and higher chip miniaturization than others. It can achieve a mixing efficiency above 0.90 (which is generally regarded as complete mixing) for low-Re solutions (flow rates ≤60 µL/min) with a mixing volume smaller than 20 nL. The time for complete mixing is in the range of milliseconds (e.g., 21 ms for Re = 10, 194 ms for Re = 0.88). The device shows negligible degradation in mixing performance for highly viscous solutions (∼50 times more viscous than water), macromolecule solutions, and colloidal solutions of nanoparticles.

2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(5): 503-508, 2022 Sep 30.
Artículo en Zh | MEDLINE | ID: mdl-36254476

RESUMEN

OBJECTIVE: Develop an intelligent equipment that can perform multiple modes of functional exercise on the knee joint, and can accurately measure and control strength, angle, angular velocity, time, frequency and so on. METHODS: Using geared motors, magnetic powder brakes and synchronous belt wheel sets and other mechanical structure and transmission technology combined with sophisticated mechanical design methods, the knee joint multiple functional exercise methods are cleverly integrated; a highly reliable PLC is used as the control core; the resistance torque out-put by the equipment is accurately controlled by adjusting the size of the exciting current; the angle sensor is used to accurately measure the rotation angle around the axis; and the error of each parameter index and the actual measured value is controlled within 5%. RESULTS: The developed prototype has a compact structure and a simple and convenient method of use. Based on the control of joint parameters such as resistance, the expected goal is achieved. CONCLUSIONS: The equipment can carry out diversified, accurate and automatic rehabilitation treatment for knee joint diseases, and has certain social and economic benefits.


Asunto(s)
Articulación de la Rodilla , Fenómenos Biomecánicos , Polvos , Rotación , Torque
3.
Indoor Air ; 30(6): 1147-1165, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32845998

RESUMEN

Microbes in buildings have attracted extensive attention from both the research community and the general public due to their close relationship with human health. However, there still lacks comprehensive information on the indoor exposure level of microbes in China. This study systematically reviews exposure levels, the community structures, and the impact factors of airborne bacteria and fungi in residences, schools, and offices in China. We reviewed the major literature databases between 1980 and 2019 and selected 55 original studies based on a set of criteria. Results show that the concentration of indoor bacteria varies from 72.5 to 7500 CFU/m3 , with a median value of 1000 CFU/m3 , and the concentration of fungi varies from 12 to 9730 CFU/m3 , with a median value of 526 CFU/m3 . The concentration level of microbes varies in different climate zones, with higher bacterial concentrations in the severe cold zone, and higher fungal concentrations in the hot summer and warm winter zone. Among different buildings, classrooms have the highest average bacteria and fungi levels. This review reveals that a unified assessment system based on health effects is needed for evaluating the exposure levels of bacteria and fungi.


Asunto(s)
Microbiología del Aire , Contaminación del Aire Interior/estadística & datos numéricos , Exposición a Riesgos Ambientales/estadística & datos numéricos , Bacterias , Monitoreo del Ambiente , Hongos , Vivienda , Humanos , Instituciones Académicas , Estaciones del Año , Lugar de Trabajo
4.
BMC Cancer ; 19(1): 1240, 2019 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-31864321

RESUMEN

BACKGROUND AND OBJECTIVE: Tumor angiogenesis is vital for tumor growth. Recent evidence indicated that bone marrow-derived mesenchymal stem cells (BMSCs) can migrate to tumor sites and exert critical effects on tumor growth through direct and/or indirect interactions with tumor cells. However, the effect of BMSCs on tumor neovascularization has not been fully elucidated. This study aimed to investigate whether fusion cells from glioma stem cells and BMSCs participated in angiogenesis. METHODS: SU3-RFP cells were injected into the right caudate nucleus of NC-C57Bl/6 J-GFP nude mice, and the RFP+/GFP+ cells were isolated and named fusion cells. The angiogenic effects of SU3-RFP, BMSCs and fusion cells were compared in vivo and in vitro. RESULTS: Fusion cells showed elevated levels of CD31, CD34 and VE-Cadherin (markers of VEC) as compared to SU3-RFP and BMSCs. The MVD-CD31 in RFP+/GFP+ cell xenograft tumor was significantly greater as compared to that in SU3-RFP xenograft tumor. In addition, the expression of CD133 and stem cell markers Nanog, Oct4 and Sox2 were increased in fusion cells as compared to the parental cells. Fusion cells exhibited enhanced angiogenic effect as compared to parental glioma cells in vivo and in vitro, which may be related to their stem cell properties. CONCLUSION: Fusion cells exhibited enhanced angiogenic effect as compared to parental glioma cells in vivo and in vitro, which may be related to their stem cell properties. Hence, cell fusion may contribute to glioma angiogenesis.


Asunto(s)
Glioma/irrigación sanguínea , Células Madre Mesenquimatosas/patología , Células Madre Neoplásicas/patología , Animales , Fusión Celular , Línea Celular Tumoral , Técnicas de Cocultivo/métodos , Glioma/metabolismo , Glioma/patología , Xenoinjertos , Humanos , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Desnudos , Células Madre Neoplásicas/metabolismo , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Microambiente Tumoral
5.
Zhonghua Zhong Liu Za Zhi ; 37(5): 336-41, 2015 May.
Artículo en Zh | MEDLINE | ID: mdl-26463022

RESUMEN

OBJECTIVE: The aim of this study was to clarify whether the fusion of bone marrow mesenchymal stem cells (MSCs) with tumor cells can promote tumor angiogensis. METHODS: Human glioma stem/progenitor cells (GSPCs) (SU3 cells) were transfected with red fluorescent protein (RFP) gene. Bone marrow mesenchymal stem cells (MSCs) were harvested from nude mice with whole-body green fluorescent protein (GFP) gene expression. Then the two kinds of cells were co-cultured in vitro. At the same time SU3-RFP was transplanted into the brain of GFP-expressing nude mice to establish xenograft tumors. The co-cultured cells, GFP/RFP double positive (yellow) cells and blood vessels obtained from the xenograft tumors were observed under fluorescent microscope and laser scanning confocal microscope. RESULTS: After five passages in vitro, MSCs maintained the proliferative activity and highly expressed CD105. CD105 was also expressed in the femurs of GFP-expressing nude mice, tumor cells, blood vessels of SU3 xenograft tumors, and clinical malignant gliomas. When MSCs were co-cultured with SU3-RFP, the ratio of yellow cells co-expressing RFP and GFP was significantly increased after extended time and continuous passages. According to the flow cytometry, yellow cells co-expressing RFP and GFP were 83.7% of the cultured cells. In tissue slices of the xenograft tumors, bundles of yellow vessel-like structure and cross-sectioned yellow vascular wall structures including vascular wall stroma cells were observed with RFP and GFP expression, and were identified as de novo formed vessels derived from fusion of MSCs with SU3-RFP cells. CONCLUSION: Cell fusion occurs between tumor cells and host MSCs and it promotes tumor angiogenesis.


Asunto(s)
Células de la Médula Ósea/fisiología , Glioma , Células Madre Mesenquimatosas , Neovascularización Patológica , Animales , Comunicación Celular , Fusión Celular , Células Cultivadas , Proteínas Fluorescentes Verdes , Humanos , Proteínas Luminiscentes , Ratones , Ratones Desnudos , Microscopía Fluorescente , Neoplasias , Células Madre , Transfección , Trasplante Heterólogo , Proteína Fluorescente Roja
6.
Eur J Nucl Med Mol Imaging ; 41(5): 972-84, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24504502

RESUMEN

PURPOSE: Growing evidence suggests that microRNAs (miRNAs) play key roles in cardiac hypertrophy. To measure the expression of endogenous miRNAs is very conducive to understanding the importance of miRNAs in cardiac hypertrophy. However, current methods to monitor endogenous miRNA levels, such as Northern blotting, quantitative real-time polymerase chain reaction (qRT-PCR), and microarrays cannot provide real-time information on miRNA biogenesis in vivo. METHODS: We constructed a miRNA reporter imaging system to monitor miR-22 expression in isoproterenol-induced cardiac hypertrophy repetitively and noninvasively. There were three copies of the antisense of miR-22 (3×PT_miR-22) cloned into the 3' untranslated region (UTR) of the Gaussia luciferase (Gluc) reporter genes under the control of the cytomegalovirus (CMV) promoter in this miRNA reporter system (CMV/Gluc/3×PT_miR-22). CMV/firefly luciferase (Fluc) was used as a positive control for imaging of miR-22 expression. Meanwhile, quantifications of miR-22 in cardiomyocyte hypertrophy and in mouse cardiac hypertrophy induced by isoproterenol stimulation were measured by qRT-PCR. Furthermore, we used this miRNA reporter imaging system to appraise the antihypertrophic effect of antagomir-22 in vitro and in vivo. RESULTS: The bioluminescence signals of the CMV/Gluc/3×PT_miR-22 were gradually decreased with prolongation of isoproterenol intervention in vitro and in vivo. Overexpression of miR-22 was observed in cardiac hypertrophy, and markedly administration of antagomir-22 could reverse the upregulation of miR-22 and its prohypertrophic effects. Furthermore, knockdown of miR-22 by antagomir-22 could markedly reverse the repressed Gluc activities in vitro and in vivo. However, the Fluc activity of CMV/Fluc was not affected with isoproterenol treatment. CONCLUSION: This study elucidates the feasibility of using our constructed miRNA reporter imaging system to monitor the location and magnitude of expression levels of miR-22 in cardiac hypertrophy in vitro and in vivo.


Asunto(s)
Cardiomegalia/metabolismo , Mediciones Luminiscentes/métodos , MicroARNs/metabolismo , Imagen de Cuerpo Entero/métodos , Animales , Cardiomegalia/inducido químicamente , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Isoproterenol/toxicidad , Luciferasas de Luciérnaga/genética , Luciferasas de Luciérnaga/metabolismo , Ratones , MicroARNs/genética
7.
ACS Appl Mater Interfaces ; 16(17): 21807-21817, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38634635

RESUMEN

Radiative cooling is the process to dissipate heat to the outer space through an atmospheric window (8-13 µm), which has great potential for energy savings in buildings. However, the traditional "static" spectral characteristics of radiative cooling materials may result in overcooling during the cold season or at night, necessitating the development of dynamic spectral radiative cooling for enhanced energy saving potential. In this study, we showcase the realization of dynamic radiative cooling by modulating the heat transfer process using a tunable transmittance convection shield (TTCS). The transmittance of the TTCS in both solar spectrum and atmospheric window can be dynamically adjusted within ranges of 28.8-72.9 and 27.0-80.5%, with modulation capabilities of ΔTsolar = 44.1% and ΔT8-13 µm = 53.5%, respectively. Field measurements demonstrate that through the modulation, the steady-state temperature of the TTCS architecture is 0.3 °C lower than that of a traditional radiative cooling architecture during the daytime and 3.3 °C higher at nighttime, indicating that the modulation strategy can effectively address the overcooling issue, offering an efficient way of energy saving through dynamic radiative cooling.

8.
Front Bioeng Biotechnol ; 12: 1374352, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694621

RESUMEN

Background: The treatment of patellar tendon injury has always been an unsolved problem, and mechanical characterization is very important for its repair and reconstruction. Elastin is a contributor to mechanics, but it is not clear how it affects the elasticity, viscoelastic properties, and structure of patellar tendon. Methods: The patellar tendons from six fresh adult experimental pigs were used in this study and they were made into 77 samples. The patellar tendon was specifically degraded by elastase, and the regional mechanical response and structural changes were investigated by: (1) Based on the previous study of elastase treatment conditions, the biochemical quantification of collagen, glycosaminoglycan and total protein was carried out; (2) The patellar tendon was divided into the proximal, central, and distal regions, and then the axial tensile test and stress relaxation test were performed before and after phosphate-buffered saline (PBS) or elastase treatment; (3) The dynamic constitutive model was established by the obtained mechanical data; (4) The structural relationship between elastin and collagen fibers was analyzed by two-photon microscopy and histology. Results: There was no statistical difference in mechanics between patellar tendon regions. Compared with those before elastase treatment, the low tensile modulus decreased by 75%-80%, the high tensile modulus decreased by 38%-47%, and the transition strain was prolonged after treatment. For viscoelastic behavior, the stress relaxation increased, the initial slope increased by 55%, the saturation slope increased by 44%, and the transition time increased by 25% after enzyme treatment. Elastin degradation made the collagen fibers of patellar tendon become disordered and looser, and the fiber wavelength increased significantly. Conclusion: The results of this study show that elastin plays an important role in the mechanical properties and fiber structure stability of patellar tendon, which supplements the structure-function relationship information of patellar tendon. The established constitutive model is of great significance to the prediction, repair and replacement of patellar tendon injury. In addition, human patellar tendon has a higher elastin content, so the results of this study can provide supporting information on the natural properties of tendon elastin degradation and guide the development of artificial patellar tendon biomaterials.

9.
Cell Physiol Biochem ; 31(6): 997-1008, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23860036

RESUMEN

BACKGROUND: Growing evidence shows that microRNAs (miRNAs) are involved in various cardiac processes including cardiac hypertrophy. However, the modulation of miRNA by pharmacological intervention in cardiomyocyte hypertrophy has not been disclosed yet. methods: We constructed neonatal rat cardiomyocyte hypertrophy induced by angiotensin II stimulation and subjected to cardiomyocyte immunochemistry, qRT-PCR and immunoblotting analysis. In addition, we constructed the mouse cardiac hypertrophy using angomir-22 stimulation and demonstrated the potential antihypertrophic mechnism of atorvastatin. RESULTS: The results showed that a collection of miRNAs were aberrantly expressed in hypertrophic cardiomyocytes induced by angiotensin II stimulation. In addition, overexpression of miR-22 was found in angiotensin II-induced hypertrophic cardiomyocytes, whereas administration of atorvastatin could reverse the upregulation of miRNA-22 nearly back to the control level. Furthermore, up-regulation of miRNA-22 in cardiomyocytes in vitro and in vivo could induce cardiac hypertrophy, which could suppress the protein level of phosphatase and tensin homolog deleted on chromosome ten (PTEN). Concomitantly, the production of ANP, BNP and ß-MHC was enhanced and cardiomyocyte size was increased. However, atorvastatin could markedly knockdown miRNA-22 expression and reverse these changes in cardiomyocytes. These results suggest that the contribution of atrovastatin to cardiomyocyte hypertrophy may be involved in downregulation of miRNA-22 expression, which modulates the activity of PTEN in cardiomyocyte hypertrophy. conclusion: This study demonstrates for the first time the modulation of miRNA-22 can be achieved by pharmacological intervention. The data generated from this study provides a rationale for the development of miRNA-based strategies for antihypertrophic treatment.


Asunto(s)
Anticolesterolemiantes/farmacología , Cardiomegalia/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Ácidos Heptanoicos/farmacología , MicroARNs/metabolismo , Pirroles/farmacología , Angiotensina II/toxicidad , Animales , Atorvastatina , Factor Natriurético Atrial/genética , Factor Natriurético Atrial/metabolismo , Cardiomegalia/inducido químicamente , Cardiomegalia/patología , Células Cultivadas , Modelos Animales de Enfermedad , Masculino , Ratones , MicroARNs/antagonistas & inhibidores , Miocardio/patología , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Cadenas Pesadas de Miosina/genética , Cadenas Pesadas de Miosina/metabolismo , Péptido Natriurético Encefálico/genética , Péptido Natriurético Encefálico/metabolismo , Oligonucleótidos Antisentido/metabolismo , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Monoéster Fosfórico Hidrolasas/genética , Monoéster Fosfórico Hidrolasas/metabolismo , Ratas
10.
J Nanosci Nanotechnol ; 13(2): 1339-42, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23646632

RESUMEN

Nitrile-butadiene-rubber composites, filled with super conducting carbon black, are successfully prepared with low percolation threshold, high conductivity and electromagnetic shielding effectiveness. Percolation theory is used to represent the system's conductivity, and the corresponding result is close to the experimental value. The fitting curve also gives the weight fraction threshold and conductivity exponent of the conducting polymer. The percolation threshold of the composite is 9.2 phr, which is much smaller than previous homologous findings and lower than the value of short carbon fiber counterparts reported. The volume resistivity becomes 3.17 omega x cm for the 20 phr sample and decreases to 0.66 omega x cm for the 40 phr sample. At 1.8 GHz for 40 phr sample, the shielding effectiveness is -43 dB.

11.
J Ultrasound Med ; 32(11): 1951-6, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24154899

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the changes in myocardial function in patients after coronary artery bypass graft (CABG) surgery using longitudinal and circumferential strain on speckle-tracking imaging. METHODS: A total of 145 patients who successfully underwent CABG surgery with a left ventricular ejection fraction (LVEF) of 50% or greater were enrolled in this study. Patients were classified into 4 groups based on age: group 1 (33-59 years), group 2 (60-64 years), group 3 (65-69 years), and group 4 (70-79 years). Routine echocardiography and longitudinal and circumferential strain measurements on speckle-tracking imaging were performed 1 week before and 1, 3, and 6 months after the CABG. RESULTS: In all groups, longitudinal strain increased significantly at 3 and 6 months after CABG therapy compared to baseline (P < .05). A significant increase in circumferential strain was found 1 month after the CABG in groups 1, 2, and 3, and a continuous increase in the parameter was observed in all groups 3 months after therapy (P < .05). However, the LVEF, left ventricular end-diastolic dimension, and stroke volume measured by routine echocardiography were not significantly changed after successful CABG treatment in all groups during 6 months of follow-up. CONCLUSIONS: Based on the results of our study in all age groups, speckle-tracking imaging parameters are more effective than the LVEF, left ventricular end-diastolic dimension, and stroke volume for monitoring improvement in myocardial function after CABG surgery.


Asunto(s)
Puente de Arteria Coronaria/estadística & datos numéricos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/cirugía , Ecocardiografía/estadística & datos numéricos , Diagnóstico por Imagen de Elasticidad/estadística & datos numéricos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/cirugía , Adulto , Anciano , China/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Resultado del Tratamiento , Disfunción Ventricular Izquierda/epidemiología
12.
Science ; 382(6671): 644-645, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37943902

RESUMEN

Microporous ceramics passively cool buildings and reduce the need for air conditioners.

13.
Micromachines (Basel) ; 14(1)2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36677280

RESUMEN

Hydrogel-based evaporative cooling with a low carbon footprint is regarded as a promising technology for thermal regulation. Yet, the efficiency of hydrogel regeneration at night generally mismatches with vapor evaporation during the day, resulting in a limited cooling time span, especially in arid regions. In this work, we propose an efficient approach to improve hydrogel cooling performance, especially the cooling time span, with a bilayer structure, which comprises a bottom hydrogel layer and an upper aerogel layer. The microporous aerogel layer can reduce the saturation vapor density at the hydrogel surface by employing daytime radiative cooling, together with increased convective heat transfer resistance by thermal insulation, thus boosting the duration of evaporative cooling. Specifically, the microstructure of porous aerogel for efficient radiative cooling and vapor transfer is synergistically optimized with a cooling performance model. Results reveal that the proposed structure with a 2-mm-thick SiO2 aerogel can reduce the temperature by 1.4 °C, meanwhile extending the evaporative cooling time span by 11 times compared to a single hydrogel layer.

14.
Zhongguo Zhen Jiu ; 43(6): 721-6, 2023 Jun 12.
Artículo en Zh | MEDLINE | ID: mdl-37313569

RESUMEN

A multifunctional moxibustion treatment machine is designed and developed to assist the heat-sensitive moxibustion therapy. Through the motion control of the stepping motor by programmable logic controller (PLC), the automatic control is obtained for the acupoint detection of heat-sensitive moxibustion therapy and the manual operation of moxibustion. The skin temperature is monitored in real-time, using infrared non-contact temperature measurement technology. Based on the deviation of the temperature set value and the monitoring one, the distance between the moxibustion device and the exerted region is adjusted automatically by PLC so that the temperature is controlled practically. The multifunctional moxibustion treatment machine based on the heat-sensitive moxibustion therapy is capable of the operation control of mild moxibustion, circling moxibustion, sparrow-pecking moxibustion and along-meridian moxibustion techniques, as well as real-time monitoring of skin temperature. The temperature change curve of this machine is coincident with that obtained by the manual operation of heat-sensitive moxibustion. This multifunctional moxibustion treatment machine assists the delivery of heat-sensitive moxibustion therapy and it is satisfactory in temperature control and precise in operation.


Asunto(s)
Meridianos , Moxibustión , Calor , Manejo del Dolor , Puntos de Acupuntura
15.
ACS Nano ; 17(18): 18308-18317, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37703206

RESUMEN

Climate change has recently caused more and more severe temperatures, inducing a growing demand for personal thermal management at outdoors. However, designing textiles that can achieve personal thermoregulation without energy consumption in severely hot and cold environments remains a huge challenge. Herein, a hierarchically nanofibrous (HNF) textile with improved thermal insulation and radiative thermal management functions is fabricated for efficient personal thermal management in severe temperatures. The textile consists of a radiative cooling layer, an intermediate thermal insulation layer, and a radiative heating layer, wherein the porous lignocellulose aerogel membrane (LCAM) as intermediate layer has low thermal conductivity (0.0366 W·m-1·K-1), ensuring less heat loss in cold weather and blocking external heat in hot weather. The introduction of polydimethylsiloxane (PDMS) increases the thermal emissivity (90.4%) of the radiative cooling layer in the atmospheric window and also endows it with a perfect self-cleaning performance. Solar absorptivity (80.1%) of the radiative heating layer is dramatically increased by adding only 0.05 wt% of carbon nanotubes (CNTs) into polyacrylonitrile. An outdoor test demonstrates that the HNF textile can achieve a temperature drop of 7.2 °C compared with white cotton in a hot environment and can be as high as 12.2 °C warmer than black cotton in a cold environment. In addition, the HNF textile possesses excellent moisture permeability, breathability, and directional perspiration performances, making it promising for personal thermal management in severely hot and cold environments.

16.
Front Neurosci ; 17: 1125281, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37274215

RESUMEN

Background: Alzheimer's disease (AD), a neurodegenerative disorder with progressive symptoms, seriously endangers human health worldwide. AD diagnosis and treatment are challenging, but molecular biomarkers show diagnostic potential. This study aimed to investigate AD biomarkers in the peripheral blood. Method: Utilizing three microarray datasets, we systematically analyzed the differences in expression and predictive value of mitophagy-related hub genes (MRHGs) in the peripheral blood mononuclear cells of patients with AD to identify potential diagnostic biomarkers. Subsequently, a protein-protein interaction network was constructed to identify hub genes, and functional enrichment analyses were performed. Using consistent clustering analysis, AD subtypes with significant differences were determined. Finally, infiltration patterns of immune cells in AD subtypes and the relationship between MRHGs and immune cells were investigated by two algorithms, CIBERSORT and single-sample gene set enrichment analysis (ssGSEA). Results: Our study identified 53 AD- and mitophagy-related differentially expressed genes and six MRHGs, which may be potential biomarkers for diagnosing AD. Functional analysis revealed that six MRHGs significantly affected biologically relevant functions and signaling pathways such as IL-4 Signaling Pathway, RUNX3 Regulates Notch Signaling Pathway, IL-1 and Megakaryocytes in Obesity Pathway, and Overview of Leukocyteintrinsic Hippo Pathway. Furthermore, CIBERSORT and ssGSEA algorithms were used for all AD samples to analyze the abundance of infiltrating immune cells in the two disease subtypes. The results showed that these subtypes were significantly related to immune cell types such as activated mast cells, regulatory T cells, M0 macrophages, and neutrophils. Moreover, specific MRHGs were significantly correlated with immune cell levels. Conclusion: Our findings suggest that MRHGs may contribute to the development and prognosis of AD. The six identified MRHGs could be used as valuable diagnostic biomarkers for further research on AD. This study may provide new promising diagnostic and therapeutic targets in the peripheral blood of patients with AD.

17.
Artículo en Inglés | MEDLINE | ID: mdl-37910847

RESUMEN

Radiative cooling is a promising technology that offers benefits such as reducing cooling energy demand, mitigating climate change impacts, and contributing to sustainable development. However, previous radiative cooling technologies are unable to manage humidity, which is crucial and energy-intensive in many applications. Therefore, it is necessary to extend the capabilities of radiative coolers to include humidity control. Here, we demonstrate a fiber-encapsulated gel structure (FEGS) to realize simultaneous radiative cooling and humidity control. By employing a phase equilibrium-based strategy, the FEGS can control relative humidity to any value between 30 and 80%. The changes in temperature, thermal conductivity, and water content during the regeneration process of FEGS were studied. Field tests demonstrated that the FEGS can achieve 5 °C subambient temperature reduction under direct sunlight while maintaining the relative humidity at a controlled level of 58 ± 3% for a continuous period of 3 days. This work can potentially pave the way for the comanagement of temperature and humidity in a passive, low-cost, and scalable way.

19.
Front Bioeng Biotechnol ; 11: 1172013, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37229497

RESUMEN

Objective: To evaluate the biomechanical effects of Poller screws (PS) combined with small-diameter intramedullary nails in the treatment of distal tibial fractures at different locations and on different planes. Methods: Nine finite element (FE) models were used to simulate the placement of the intramedullary nail (IMN) and the PS for distal tibial fractures. Structural stiffness and interfragmentary motion (IFM) through the fracture were investigated to assess the biomechanical effects of the PS. The allowable stress method was used to evaluate the safety of the construct. Results: With the axial load of 500 N, the mean axial stiffness of IMN group was 973.38 ± 95.65 N/mm, which was smaller than that at positions A and B of the coronal group and sagittal group (p < 0.05). The shear IFM of the IMN group was 2.10 ± 0.02 mm, which were smaller than that at positions A and B of the coronal group and sagittal group (p < 0.05). Under physiological load, the stresses of all internal fixation devices and the nail-bone interface were within a safe range. Conclusion: In the treatment of distal tibial fractures, placing the PS in the proximal fracture block can obtain better biomechanical performance. The IMN fixation system can obtain higher structural stiffness and reduce the IFM of the fracture end by adding PS.

20.
ACS Appl Mater Interfaces ; 15(22): 26863-26871, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37230959

RESUMEN

As the global energy crisis intensifies, the development of solar energy has become a vital area of focus for many nations. The utilization of phase change materials (PCMs) for photothermal energy storage in the medium temperature range holds great potential for various applications, but their conventional forms face several challenges. For instance, the longitudinal thermal conductivity of photothermal PCMs is inadequate for effective heat storage on the photothermal conversion surface, and there is a risk of leakage due to repeated solid-liquid phase transitions. Here, we report a solid-solid phase change material, tris(hydroxymethyl)aminomethane (TRIS), which has a phase change temperature of 132 °C in the medium temperature range, enabling high-grade and stable solar energy storage. To overcome the low thermal conductivity problem, we propose a large-scale production of oriented high thermal conductivity composites by compressing a mixture of TRIS and expanded graphite (EG) using the pressure induction method to create in-plane highly thermally conductive channels. Remarkably, the resulting phase change composites (PCCs) exhibit a directional thermal conductivity of 21.3 W/(m·K). Furthermore, the high phase change temperature (132 °C) and large phase change entropy (213.47 J/g) enable a large-capacity high-grade thermal energy to be used. The developed PCCs, when combined with selected photo-absorbers, exhibit efficient integration of solar-thermal conversion and storage. Additionally, we also demonstrated a solar-thermoelectric generator device with an energy output of 93.1 W/m2, which is close to the power of photovoltaic systems. Overall, this work provides a technological route to the large-scale fabrication of mid-temperature solar energy storage materials with high thermal conductivity, high phase change enthalpy, and no risk of leakage, and also offers a potential alternative to photovoltaic technology.

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