Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 184
Filtrar
1.
BMC Genomics ; 25(1): 320, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549066

RESUMO

BACKGROUND: Stigma exsertion is an essential agricultural trait that can promote cross-pollination to improve hybrid seed production efficiency. However, the molecular mechanism controlling stigma exsertion remains unknown. RESULTS: In this study, the Nicotiana tabacum cv. K326 and its two homonuclear-heteroplasmic lines, MSK326 (male-sterile) and MSK326SE (male-sterile and stigma exserted), were used to investigate the mechanism of tobacco stigma exsertion. A comparison of the flowers between the three lines showed that the stigma exsertion of MSK326SE was mainly due to corolla shortening. Therefore, the corollas of the three lines were sampled and presented for RNA-seq analysis, which found 338 candidate genes that may cause corolla shortening. These genes were equally expressed in K326 and MSK326, but differentially expressed in MSK326SE. Among these 338 genes, 15 were involved in hormone synthesis or signal transduction pathways. Consistently, the content of auxin, dihydrozeatin, gibberellin, and jasmonic acid was significantly decreased in the MSK326SE corolla, whereas abscisic acid levels were significantly increased. Additionally, seven genes involved in cell division, cell cycle, or cell expansion were identified. Protein-protein interaction network analysis identified 45 nodes and 79 protein interactions, and the largest module contained 20 nodes and 52 protein interactions, mainly involved in the hormone signal transduction and pathogen defensive pathways. Furthermore, a putative hub gene coding a serine/threonine-protein kinase was identified for the network. CONCLUSIONS: Our results suggest that hormones may play a key role in regulating tobacco stigma exsertion induced by corolla shortening.


Assuntos
Nicotiana , Transcriptoma , Nicotiana/genética , Revelação , Ácidos Indolacéticos/metabolismo , Hormônios/metabolismo , Flores/metabolismo
2.
Nanotechnology ; 35(16)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38150735

RESUMO

ß-Ga2O3has been widely investigated for its stability and thermochemical properties. However, the preparation ofß-Ga2O3thin films requires complex growth techniques and high growth temperatures, and this has hindered the application ofß-Ga2O3thin films. In this study,ß-Ga2O3thin films with good crystalline quality were prepared using a green method, and an ultraviolet (UV) detector based onß-Ga2O3with a photocurrent of 2.54 × 10-6A and a dark current of 1.19 × 10-8A has been developed. Two-dimensional materials have become premium materials for applications in optoelectronic devices due to their high conductivity. Here, we use the suitable energy band structure between Nb2C and Ga2O3to create a high carrier migration barrier, which reduces the dark current of the device by an order of magnitude. In addition, the device exhibits solar-blind detection, high responsiveness (28 A W-1) and good stability. Thus, the Nb2C/ß-Ga2O3heterojunction is expected to be one of the promising devices in the field of UV photoelectric detection.

3.
Oral Dis ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225738

RESUMO

OBJECTIVES: Tumor-associated neutrophils (TANs) are among the most abundant inflammatory cells in tumor microenvironment (TME). Aldehyde dehydrogenase 3A1 (ALDH3A1) is significantly reduced in oral squamous cell carcinoma (OSCC), ALDH3A1 overexpression suppresses tumorigenesis by inhibiting inflammation. This study investigated the relationship and mechanisms underlying the crosstalk between ALDH3A1 and TANs in OSCC. MATERIALS AND METHODS: Immunohistochemistry and immunofluorescence were performed to investigate the abundance of TANs and the expression of ALDH3A1. dHL-60 were induced with tumor-conditioned media and recombinant IL-6/IL-8. The expression of key proteins in PI3K/AKT/NF-κB pathway were detected by RT-PCR and western blot. A xenograft model was utilized to examine the effect of ALDH3A1 on tumorigenicity and polarization of TANs. RESULTS: In patients with OSCC, TANs significantly increased and were associated with a worse prognosis. Additionally, ALDH3A1 negatively correlated with TANs infiltration and especially the N2 phenotype which was the prominent part in OSCC. Furthermore, our study demonstrated that tumor-derived IL-8 drives ALDH3A1-mediated TANs N2 polarization in the TME through PI3K/AKT/NF-κB pathway in vitro and in vivo. CONCLUSION: Our results indicate that TANs can serve as a prognostic biomarker and ALDH3A1 could be a promising therapeutic target for regulating TANs N2 polarization in antitumor therapy.

4.
Angew Chem Int Ed Engl ; 63(18): e202401331, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38456641

RESUMO

A general approach to constructing room temperature phosphorescence (RTP) materials involves the incorporation of a phosphorescent emitter into a rigid host or polymers with high glass transition temperature. However, these materials often suffer from poor processability and suboptimal mechanical properties, limiting their practical applications. In this work, we developed benzothiadiazole-based dialkene (BTD-HEA), a multifunctional phosphorescent emitter with a remarkable yield of intersystem crossing (ΦISC, 99.83 %). Its high triplet exciton generation ability and dialkene structure enable BTD-HEA to act as a photoinitiator and crosslinker, efficiently initiating the polymerization of various monomers within 120 seconds. A range of flexible phosphorescence gels, including hydrogels, organogels, ionogels, and aerogels were fabricated, which exhibit outstanding stretchability and recoverability. Furthermore, the unique fluorescent-phosphorescent colorimetric properties of the gels provide a more sensitive method for the visual determination of the polymerization process. Notably, the phosphorescent emission intensity of the hydrogel can be increased by the formation of ice, allowing for the precise detection of hydrogel freezing. The versatility of this emitter paves the way for fabricating various flexible phosphorescence gels with diverse morphologies using microfluidics, film-shearing, roll coating process, and two/three-dimensional printing, showcasing its potential applications in the fields of bioimaging and bioengineering.

5.
Angew Chem Int Ed Engl ; 63(5): e202317431, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38081786

RESUMO

Organic near-infrared room temperature phosphorescence (RTP) materials offer remarkable advantages in bioimaging due to their characteristic time scales and background noise elimination. However, developing near-infrared RTP materials for deep tissue imaging still faces challenges since the small band gap may increase the non-radiative decay, resulting in weak emission and short phosphorescence lifetime. In this study, fused-ring pyrrole-based structures were employed as the guest molecules for the construction of long wavelength emissive RTP materials. Compared to the decrease of the singlet energy level, the triplet energy level showed a more effectively decrease with the increase of the conjugation of the substituent groups. Moreover, the sufficient conjugation of fused ring structures in the guest molecule suppresses the non-radiative decay of triplet excitons. Therefore, a near-infrared RTP material (764 nm) was achieved for deep penetration bioimaging. Tumor cell membrane is used to coat RTP nanoparticles (NPs) to avoid decreasing the RTP performance compared to traditional coating by amphiphilic surfactants. RTP NPs with tumor-targeting properties show favorable phosphorescent properties, superior stability, and excellent biocompatibility. These NPs are applied for time-resolved luminescence imaging to eliminate background interference with excellent tissue penetration. This study provides a practical solution to prepare long-wavelength and long-lifetime organic RTP materials and their applications in bioimaging.


Assuntos
Luminescência , Nanopartículas , Membrana Celular , Pirróis
6.
Funct Integr Genomics ; 23(3): 199, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37278873

RESUMO

Silicosis is an occupational lung disease that is common worldwide. In recent years, coronavirus disease 2019 (COVID-19) has provided daunting challenges to public healthcare systems globally. Although multiple studies have shown a close link between COVID-19 and other respiratory diseases, the inter-relational mechanisms between COVID-19 and silicosis remain unclear. This study aimed to explore the shared molecular mechanisms and drug targets of COVID-19 and silicosis. Gene expression profiling identified four modules that were most closely associated with both diseases. Furthermore, we performed functional analysis and constructed a protein-protein interaction network. Seven hub genes (budding uninhibited by benzimidazoles 1 [BUB1], protein regulator of cytokinesis 1 [PRC1], kinesin family member C1 [KIFC1], ribonucleotide reductase regulatory subunit M2 [RRM2], cyclin-dependent kinase inhibitor 3 [CDKN3], Cyclin B2 [CCNB2], and minichromosome maintenance complex component 6 [MCM6]) were involved in the interaction between COVID-19 and silicosis. We investigated how diverse microRNAs and transcription factors regulate these seven genes. Subsequently, the correlation between the hub genes and infiltrating immune cells was explored. Further in-depth analyses were performed based on single-cell transcriptomic data from COVID-19, and the expression of hub-shared genes was characterized and located in multiple cell clusters. Finally, molecular docking results reveal small molecular compounds that may improve COVID-19 and silicosis. The current study reveals the common pathogenesis of COVID-19 and silicosis, which may provide a novel reference for further research.


Assuntos
COVID-19 , Silicose , Humanos , COVID-19/genética , Simulação de Acoplamento Molecular , Mapas de Interação de Proteínas/genética , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Silicose/genética
7.
Opt Lett ; 48(3): 696-699, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723566

RESUMO

With the success of the Webb telescope, dispersed fringe sensing (DFS), with the significant merit of a large capture range, is proving to be a promising cophasing approach for a large-aperture segmented telescope. In this Letter, a novel, to the best of our knowledge, piston error extraction method based on principal component analysis (PCA) technology is proposed. In this method, all the one-dimension intensity distributions along the dispersion axis for different interference positions are regarded as a set of random phase-shifted interference signals. PCA technology is utilized to obtain its corresponding continuous principal phase and the piston error could be directly estimated proportionally from the slope of the phase-wavenumber line. This method avoids nonlinear operations, similar to Shi's traditional framework; no active move is needed for fine cophasing, and the method is also free of characteristic constant calibration in sidelobe peak displacement- and slope-based methods. Preliminary simulations of the method's coarse-then-fine cophasing ability with high accuracy are presented here to show its potential.

8.
Nanotechnology ; 34(36)2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37263193

RESUMO

A novel controllable magnesium silicate nanotube (MSN) material derived from coal fly ash was successfully synthesized via a hydrothermal process for the first time, and the reaction conditions and mechanism of synthesizing MSN materials from magnesium oxide and sodium silicate extracted from the fly ash were studied. The optimal preparation conditions are temperature = 220 °C, pH = 13.5, and Mg: Si molar ratio = 3:2, and the tubular structure gradually appeared and showed controllable and regular growth with the increase of synthesis time. The mechanism revealed that with the gradual dissolution of brucite into the sodium silicate solution, the reaction product begins to crystallize and transform from an initial sheet-like structure to a tubular structure, and finally becomes a uniformly arranged nanotube. The formation process of MSN follows Pauling's fourth rule, Si-O tetrahedral coordination and Mg-OH octahedral coordination is further condensed to form a two-layer structure by the action of active oxygen, then the sheet is rolled into a tube under its structural stress. The growth of both outer tubular diameter and inner tubular diameter has good linear law and controllable, and the growth rate are 0.289 nm h-1and 0.071 nm h-1, respectively.

9.
Cell Mol Biol (Noisy-le-grand) ; 69(6): 141-145, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37605578

RESUMO

This study was to explore the expression and correlation between gene Xpert MTB / RIF, ADA, and TB-DNA in TB meningitis. For this purpose, we selected 102 patients in the TB meningitis progression diagnosed and treated in our hospital from January 2019 to December 2020, and another 100 patients in the non-TB meningitis group were selected for the control experiment. Two sets of CSF samples were taken to analyze the gene Xpert MTB / RIF positive rate and the correlation between the expression and the progression of tuberculous meningitis by testing the levels of ADA and TB-DNA in the patient body using an automatic biochemical analyzer. Research indicated that The levels of gene Xpert MTB / RIF, ADA, and TB-DNA in the non-tuberculous meningitis group were lower than those in the tuberculous meningitis group (P<0.05; Levels of gene Xpert MTB / RIF, ADA, and TB-DNA were higher (P<0.05) in patients with group III tuberculous meningitis compared with those under grades I-II tuberculous meningitis, and levels of gene Xpert MTB / RIF, ADA, and TB-DNA were higher (P<0.05) in patients with group VI tuberculous meningitis compared with group III tuberculous meningitis; Gene Xpert MTB / RIF, ADA, TB-DNA) as factors occurring in TB meningitis progression, and all three were associated (P<0.05) with TB meningitis progression; Gene Xpert MTB / RIF, ADA showed a positive correlation (r = 0.296, P = 0.002); Gene Xpert MTB / RIF, TB-DNA showed a positive correlation (r = 0.422, P = 0.001); ADA, TB-DNA showed a positive correlation (r = 0.366, P = 0.001). It was concluded that Gene X-Pert MTB / RIF, ADA, and TB-DNA showed high levels in TB meningitis progression, and as the disease worsened, all three showed a positive association in TB meningitis progression.


Assuntos
DNA , Meningite , Humanos , Diagnóstico Precoce , Hospitais
10.
Sensors (Basel) ; 23(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37571510

RESUMO

The application of TiO2 nanorods in the field of ultraviolet (UV) photodetectors is hindered by a high dark current, which is attributed to crystal surface defects and intrinsic excitation by carrier thermal diffusion. Here, a photodetector based on polycrystalline perovskite MAPbCl3/TiO2 nanorods heterojunctions has been fabricated to overcome the shortcoming. The structure was composed of horizontal MAPbCl3 polycrystalline and vertically aligned TiO2 nanorods array. Many localized depletion regions at the MAPbCl3/TiO2 interface can reduce the dark current. The TiO2/MAPbCl3 detector shows high performance including a high ratio of light-dark current of about six orders of magnitude, which is much larger than that of the TiO2 detector. This study indicates the potential in the TiO2/MAPbCl3 heterojunction to fabricate high-performance UV detectors.

11.
Molecules ; 28(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36985721

RESUMO

The occurrence of sulfur in coal direct liquefaction residue affects its further high quality and high value utilization. Electrochemical desulfurization is characterized by mild reaction conditions, simple operation, easy separation of sulfur conversion products and little influence on the properties of the liquefied residue. An anodic electrolytic oxidation desulphurization experiment was carried out on the liquefaction residue of the by-product of a coal-to-liquid enterprise in the slurry state. An electrochemical test and material characterization of raw materials before and after electrolysis showed that electrolytic oxidation can desulfurize the liquefaction residue under an alkaline condition. Linear sweep voltammetry (LSV) was used for the electrolysis experiments to obtain the optimal slurry concentration of 60 g/L. On this basis, the reaction kinetics were calculated, and the minimum activation energy in the interval at 0.9 (V vs. Hg/HgO) was 19.71 kJ/mol. The relationship between the electrolytic desulfurization of the liquefied residue and energy consumption was studied by the potentiostatic method. The influence of anodic potential and electrolytic temperature on the current density, cell voltage, desulfurization rate and energy consumption was investigated. The experimental results showed that the desulfurization rate and total energy consumption increase positively with the increase in reaction temperature and electrolytic potential in a certain range. The influence of the reaction temperature on the desulfurization rate and total energy consumption is more prominent than that of electrolytic potential, but the energy consumption of sulfur removal per unit mass does not show a positive correlation. Therefore, with the energy consumption per unit mass of sulfur removal as the efficiency index, the optimal experimental results were obtained: under the conditions of 0.8 (V vs. Hg/HgO) anode potential, 50 °C electrolytic temperature, 60 g/L slurry concentration and 14,400 s electrolytic time, the desulfurization rate was 18.85%, and the power consumption per unit mass of sulfur removal was 5585.74 W·s/g. The results of XPS, SEM, BET and IC showed that both inorganic and organic sulfur were removed by electrolytic oxidation, and the morphology, pore structure and chemical bond of the liquefied residue were affected by electrolytic oxidation. The research method provides a new idea and reference for the efficiency evaluation of desulfurization and hydrogen production from coal liquefaction residue.

12.
Angew Chem Int Ed Engl ; 62(50): e202314273, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37885123

RESUMO

The development of flexible, room-temperature phosphorescence (RTP) materials remains challenging owing to the quenching of their unstable triplet excitons via molecular motion. Therefore, a polymer matrix with Tg higher than room temperature is required to prevent polymer segment movement. In this study, a RTP material was developed by incorporating a 4-biphenylboronic acid (BPBA) phosphor into a poly(vinylidene fluoride) (PVDF) matrix (Tg =-27.1 °C), which exhibits a remarkable UV-light-dependent oxygen consumption phosphorescence with a lifetime of 1275.7 ms. The adjustable RTP performance is influenced by the crystallinity and polymorph (α, ß, and γ phases) fraction of PVDF, therefore, the low Tg of the PVDF matrix enables the polymeric segmental motion upon microwave irradiation. Consequently, a reduction in the crystallinity and an increase in the α phase fraction in PVDF film induces RTP after 2.45 GHz microwave irradiation. These findings open up new avenues for constructing crystalline and phase-dependent RTP materials while demonstrating a promising approach toward microwave detection.

13.
J Am Chem Soc ; 144(13): 6107-6117, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35316063

RESUMO

Long-lived organic room-temperature phosphorescence (RTP) has sparked intense explorations, owing to the outstanding optical performance and exceptional applications. Because triplet excitons in organic RTP experience multifarious relaxation processes resulting from their high sensitivity, spin multiplicity, inevitable nonradiative decay, and external quenchers, boosting RTP performance by the modulated triplet-exciton behavior is challenging. Herein, we report that cross-linked polyphosphazene nanospheres can effectively promote long-lived organic RTP. Through molecular engineering, multiple carbonyl groups (C═O), heteroatoms (N and P), and heavy atoms (Cl) are introduced into the polyphosphazene nanospheres, largely strengthening the spin-orbit coupling constant by recalibrating the electronic configurations between singlet (Sn) and triplet (Tn) excitons. In order to further suppress nonradiative decay and avoid quenching under ambient conditions, polyphosphazene nanospheres are encapsulated with poly(vinyl alcohol) matrix, thus synchronously prompting phosphorescence lifetime (173 ms longer), phosphorescence efficiency (∼12-fold higher), afterglow duration time (more than 20 s), and afterglow absolute luminance (∼19-fold higher) as compared with the 2,3,6,7,10,11-hexahydroxytriphenylene precursor. By measuring the emission intensity of the phosphorescence, an effective probe based on the nanospheres is developed for visible, quantitative, and expeditious detection of volatile organic compounds. More significantly, the obtained films show high selectivity and robustness for anisole detection (7.1 × 10-4 mol L-1). This work not only demonstrates a way toward boosting the efficiency of RTP materials but also provides a new avenue to apply RTP materials in feasible detection applications.

14.
Biochem Biophys Res Commun ; 610: 1-7, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35461070

RESUMO

Inevitable emergence of drug resistance is the biggest hurdle to both chemotherapies and targeted therapies. Understanding the resistance mechanisms will contribute to identification of biomarkers for predicting response to therapy and design new therapeutic strategies to overcome drug resistance in human cancers. The type II transforming growth factor (TGF)-ß receptor gene (TGFBR2) is frequently frameshift mutated in several cancer types, especially in colorectal, endometrium and gastric cancers cells. Here, we found that Med12, a component of the transcriptional mediator complex, plays a role in modulating chemosensitivity in TGFBR2 deficient cancer cells. Loss of Med12 leads to chemoresistance in multiple TGFBR2 deficient cancer cells. Interestingly, RNA sequencing data revealed that interferon IFN-related DNA damage resistance signature (IRDS) is upregulated in Med12 knockdown cancer cells. And the expression of IRDS pattern is negatively correlated with chemosensitivity. Therefore, our study identifies a novel mechanism of Med12-mediated drug resistance, which is a TGFBR-independent manner.


Assuntos
Complexo Mediador , Neoplasias , Receptor do Fator de Crescimento Transformador beta Tipo II , Resistencia a Medicamentos Antineoplásicos , Humanos , Complexo Mediador/genética , Complexo Mediador/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo
15.
Opt Lett ; 47(6): 1466-1469, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290339

RESUMO

The Shack-Hartmann wavefront sensor (SH-WFS) is widely used as a slope-based wavefront sensing device. The modal method is favored for wavefront reconstruction from SH-WFS output because of its excellent performance. In this case, the calibration of modal (commonly Zernike modes) slope is required in advance. Traditional numerical or symbolic integral-based methods are not satisfactory because of their low accuracy or efficiency, particularly when an extremely large number of microlenses are involved. In this Letter, a novel method based on matrix product is proposed in which two key matrix operators are utilized. The first, namely the derivative matrix operator, is used to obtain the derivative of the Zernike modes; the second, that is, the transformation matrix operator, is then used to map the Zernike derivative defined in the original, whole circular pupil into modes defined in a scaled, translated circle pupil enveloping a specific microlens. With these two operators, the evaluation of slope response of Zernike modes could be unified into a matrix-product framework, which contributes its high efficiency. Numerical simulations show the superior advantages of the proposed method in accuracy and efficiency over traditional ones.

16.
Paediatr Perinat Epidemiol ; 36(3): 390-398, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34431114

RESUMO

BACKGROUND: For initial respiratory management, continuous positive airway pressure (CPAP) is increasingly used for preterm infants, especially for gestational age less than 32 weeks. However, neonatologists are concerned about the potential risks of CPAP support failure. OBJECTIVES: To examine the association between different initial respiratory support modalities and the outcomes of preterm infants at <32 weeks of gestation across multiple neonatal intensive care units (NICU) in China. METHODS: This study was carried out over a period of 12 months in 2018. Unadjusted relative risks (RR) for demographic and clinical characteristics were calculated for CPAP failure and CPAP success in the total cohort using log-linear model based on generalised estimating equations for clustered observations. RESULTS: Among 1560 preterm infants delivered at <32 weeks, the incidence of CPAP failure was 10.3%. After adjustment for demographic and clinical factors, the relative risk of mortality (RR 7.54, 95% CI 5.56, 10.44), pneumothorax (RR 9.85, 95% CI 2.89, 61.53), pulmonary haemorrhage (RR 7.78, 95% CI 4.51, 14.64) and BPD (RR 3.65, 95% CI 3.65, 4.51) were considerably higher for infants in the CPAP failure group than those in the CPAP-S group. However, the risk of poor outcomes in CPAP failure infants was similar to that of those in the initial mechanical ventilation (MV) group. CONCLUSIONS: Continuous positive airway pressure failure was associated with an increased risk of mortality and major morbidities, including BPD, pulmonary haemorrhage and pneumothorax, and was comparable to the risk associated with initial MV.


Assuntos
Pneumotórax , Síndrome do Desconforto Respiratório do Recém-Nascido , Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Feminino , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Pneumotórax/etiologia , Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/complicações , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/terapia , Estudos Retrospectivos
17.
Nanotechnology ; 33(31)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35447608

RESUMO

In this work, we used nanocomposite saturable absorbers (SAs) in order to precisely design and modulate the process of compositing the light absorption by band gap engineering. Due to the higher absorption intensity of our MoS2/MXene nanocomposite, we have successfully shortened the pulse duration (1.2µs) of SA with enhancing saturable absorption intensity (7.22 MW cm-2), and the ultra-fast fiber laser based on this nanocomposite SA has shown wider Q-switching stable range in the case of high pump power. This strategy can efficiently improve the performance of SA and shows the potential application prospect of nanocomposites in nonlinear optics.

18.
Lasers Med Sci ; 37(9): 3433-3442, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35816215

RESUMO

The study aimed to design a reliable and straightforward PBM method by implanting a medical scattering fiber above surgically exposed spinal cord in SCI patients. Moreover, the safety of this method was examined. Twelve patients with acute SCI (ASIA B) requiring posterior decompression were recruited. The medical scattering fiber was implanted above the spinal cord, and was continuously irradiated at 810 nm, 300 mW, 30 min/day, once per day for 7 days. The vital signs (temperature, blood pressure, respiratory rate, heart rate, and oxygen saturation), infection indicators (WBC, NEUT, hs-CRP, and PCT), photo-allergic reaction indicators (Eosinophil and Basophil), coagulation function indicators (PT, APTT, TT) and neurological stability indicators (ASIA sensory and motor scores) were recorded to evaluate the safety of PBM. Three months after surgery, 12 patients completed follow-up. In our study, direct PBM on SCI site did not cause clinically pathologic changes in vital signs of the patients. All patients had higher WBC, NEUT, and hs-CRP at day 3 during irradiation than those before surgery, and returned to normal at day 7. The changes in Eosinophil and Basophil that were closely associated with allergic reactions were within normal limits throughout the course of irradiation. The coagulation function (PT, APTT, and TT) of patients were also in the normal range. The ASIA sensory and motor scores of all patients had no changes throughout the irradiation process. However, in the follow-up, both ASIA sensory and motor scores of all patients had minor improvement than those in pre-irradiation, and 7 patients had adverse events, but they were not considered to be related to PBM. Our study might firstly employ direct PBM in the SCI by using scattered optical fibers. In a limited sample size, our study concluded that direct PBM at the site of SCI would not produce adverse effects within the appropriate irradiation parameters. The method is safe, feasible, and does not add additional trauma to the patient. Our preliminary study might provide a new methodology for the clinical PBM treatment of acute SCI.


Assuntos
Proteína C-Reativa , Terapia com Luz de Baixa Intensidade , Traumatismos da Medula Espinal , Humanos , Recuperação de Função Fisiológica , Medula Espinal/patologia , Traumatismos da Medula Espinal/radioterapia , Traumatismos da Medula Espinal/patologia
19.
Sensors (Basel) ; 22(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36365833

RESUMO

In the field of ultra high accuracy inertial measurement unit (IMU), pendulous integrating gyroscopic accelerometer (PIGA) has become a research hot spot due to its high-end performance. However, PIGA is sensitive to angular velocity, and the calibration process of PIGA-based IMU will be very complicated, which makes online self-calibration difficult to implement. To solve the above problems, we proposed an online self-calibration method utilizing angular velocity observation. The main contributions of this study are twofold: (1) An error analysis of PIGA is conducted in this paper, and the error model has also been simplified to suit the self-calibration model. (2) An improved online self-calibration method utilizing angular observation based on a simplified PIGA error model is proposed in this study. Experimental results show that the self-calibration method proposed in this study can improve the PIGA online calibration accuracy effectively (with the accuracy within 0.02 m/s/pulse), which can improve the dynamic accuracy of the PIGA.

20.
Int J Mol Sci ; 23(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36077381

RESUMO

Although significant advancement has been made in the study of adipogenesis, knowledge about how chromatin accessibility regulates yak adipogenesis is lacking. We here described genome-wide dynamic chromatin accessibility in preadipocytes and adipocytes by using the assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq), and thus revealed the unique characteristics of open chromatin during yak adipocyte differentiation. The chromatin accessibility of preadipocytes and adipocytes exhibited a similar genomic distribution, displaying a preferential location within the intergenic region, intron, and promoter. The pathway enrichment analysis identified that genes with differential chromatin accessibility were involved in adipogenic metabolism regulation pathways, such as the peroxisome proliferator activated receptor-γ (PPAR) signaling pathway, wingless-type MMTV integration site (Wnt) signaling pathway, and extracellular matrix-receptor (ECM-receptor) interaction. Integration of ATAC-seq and mRNA-seq revealed that genes with a high expression were associated with high levels of chromatin accessibility, especially within 1 kb upstream and downstream of the transcription start site. In addition, we identified a series of transcription factors (TFs) related to adipogenesis and created the TF regulatory network, providing the possible interactions between TFs during yak adipogenesis. This study is crucial for advancing the understanding of transcriptional regulatory mechanisms of adipogenesis and provides valuable information for understanding the adaptation of plateau species to high-altitude environments by maintaining whole body homeostasis through fat metabolism.


Assuntos
Adipogenia , Cromatina , Adipócitos/metabolismo , Adipogenia/genética , Animais , Bovinos , Cromatina/genética , Cromatina/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Sequenciamento de Nucleotídeos em Larga Escala
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa