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1.
Anal Chem ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888085

RESUMEN

Flexible surface-enhanced Raman scattering (SERS) substrates adaptable to strains enable effective sampling from irregular surfaces, but the preparation of highly stable and sensitive flexible SERS substrates is still challenging. This paper reports a method to fabricate a high-performance strain-adaptable SERS substrate by self-assembly of Au nanoparticles (AuNPs) on polydimethylsiloxane (PDMS) nanowrinkles. Nanowrinkles are created on prestrained PDMS slabs by plasma-induced oxidation followed by the release of the prestrain, and self-assembled AuNPs are transferred onto the nanowrinkles to construct the high-performance SERS substrate. The results show that the nanowrinkled structure can improve the surface roughness and enhance the SERS signals by ∼4 times compared to that of the SERS substrate prepared on flat PDMS substrates. The proposed SERS substrate also shows good adaptability to dynamic bending up to ∼|0.4| 1/cm with excellent testing reproducibility. Phenolic pollutants, including aniline and catechol, were quantitatively tested by the SERS substrate. The self-assembled flexible SERS substrate proposed here provides a powerful tool for chemical analysis in the fields of environmental monitoring and food safety inspection.

2.
Electrophoresis ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38419136

RESUMEN

A novel optical-induced dielectrophoresis (ODEP) method employing a pressure-driven flow for the continuous separation of microparticles is presented in this study. By applying alternate current electric field on conductive indium tin oxide substrate and projecting the light geometry into the photoconductive layer, an inhomogeneous electric field is locally induced. The particles experience the dielectrophoretic force when passing through the lighting area, where the strongest electrical field gradient exists. By optimizing the structure of the lighting pattern, a stronger nonuniform electric field gradient is generated which predicts the separation of 1 and 3 µm polystyrene particles. Moreover, the effects of key parameters, including the light pattern geometry, applied voltage, and flow rate, were investigated in this study, leading to the successful sorting of 700 nm and 1 µm particles. To further examine the separation sensitivity and practicability of the proposed ODEP microfluidic method, the isolation of two different types of circulating tumor cells from T-cells and red blood cells are demonstrated, providing a novel method for the manipulation and separation of microparticles and nanoparticles.

3.
Ecotoxicol Environ Saf ; 270: 115894, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38171100

RESUMEN

Algal toxins produced by microalgae, such as domoic acid (DA)1, have toxic effects on humans. However, toxicity tests using mice only yield lethal doses of algal toxins without providing insights into the mechanism of action on cells. In this study, a fast segmentation of microfluidic flow cytometry cell images based on the bidirectional background subtraction (BBS)2 method was developed to get the visual evidence of apoptosis in both bright-field and fluorescence images. This approach enables mapping of changes in cell morphology and activity under algal toxins, allowing for fast (within 60 s) and automated biological detection. By combining microfluidics with flow cytometry, the intricate cellular-level reaction process can be observed in micro samples of 293 T cells and mouse spleen cells, offering potential for future in vitro experiments.


Asunto(s)
Microalgas , Microfluídica , Humanos , Animales , Ratones , Citometría de Flujo
4.
J Community Health Nurs ; 41(2): 82-95, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38229243

RESUMEN

PURPOSE: This study aimed to evaluate the impact of three equine therapy approaches on gross motor function in children with cerebral palsy. METHODS: The studies were retrieved from PubMed, Web of Science, Science Direct, and the Cochrane Library, in accordance with the style commonly found in scientific journal publications:(1) peer-reviewed articles written in English; (2) experimental or quasi-experimental; (3) three Equine Therapy Interventions as experiment's independent variable; (4) children with cerebral palsy; and (5) measurement of outcomes related to Gross Motor Function. RESULTS: The study examined 596 patients with cerebral palsy, whose average age was 8.03 years. The three types of horse therapy interventions had a significant impact on gross motor function in children with cerebral palsy (SMD = 0.19, 95% CI 0.02-0.36, p = 0.031). Additionally, the interventions positively affected dimensions C (SMD = 0.31, 95% CI 0.00-0.62, p = 0.05), D (SMD = 0.30, 95% CI 0.06-0.56, p = 0.017), and B (SMD = 0.72, 95% CI 0.10-1.34, p = 0.023). The Gross Motor Function Measure (GMFM) consists of 88 or 66 items, which are divided into five functional dimensions: GMFM-A (lying down and rolling), GMFM-B (sitting), GMFM-C (crawling and kneeling), GMFM-D (standing), and GMFM-E (walking, running, and jumping). Each subsection of the GMFM can be used separately to evaluate motor changes in a specific dimension of interest. Subgroup analysis revealed that different horse-assisted therapy approaches, types of cerebral palsy, exercise duration, frequency, and intervention periods are important factors influencing treatment outcomes. CONCLUSION: The intervention period ranged from 8 to 12 weeks, with session durations of 30 to 45 minutes, 2 to 3 times per week. Equine-assisted therapy (EAT) demonstrated significant improvements in the overall gross motor function score, Dimension B, Dimension C, and Dimension D among children with cerebral palsy. The most effective treatment is provided by Equine-Assisted Therapy, followed by Horseback Riding Simulator (HRS). Due to its economic practicality, HRS plays an irreplaceable role. CLINICAL EVIDENCE: Equine-Assisted Therapy (EAT) demonstrates the most effective treatment outcomes, suggesting that hospitals and healthcare professionals can form specialized teams to provide rehabilitation guidance. 2. Within equine-assisted therapy, Horseback Riding Simulator (HRS) exhibits treatment efficacy second only to Equine-Assisted Therapy (EAT), making it a cost-effective and practical option worthy of promotion and utilization among healthcare institutions and professionals. 3. In equine-assisted therapy, Therapeutic Horseback Riding (THR) holds certain value in rehabilitation due to its engaging and practical nature.


Asunto(s)
Parálisis Cerebral , Terapía Asistida por Caballos , Niño , Humanos , Caballos , Animales , Destreza Motora , Parálisis Cerebral/rehabilitación , Resultado del Tratamiento
5.
Proteomics ; 23(1): e2200204, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36408942

RESUMEN

Exosomes derived from mesenchymal stem cells (MSCs) have been used for cancer treatment, however, an in-depth analysis of the exosomal proteomes is lacking. In this manuscript, we use the diaPASEF (parallel accumulation serial fragmentation combined with the data-independent acquisition) method to quantify exosomes derived from human umbilical cord mesenchymal stem cells (UCMSCs) and rat bone marrow stem cells (BMSCs), resulting in identification of 4200 human proteins and 5362 rat proteins. Comparison of human exosomal proteins and total cellular proteins reveals that some proteins exist in the exosomes exclusively that can be served as potential markers for exosomes. Quantitative proteomic analysis of exosomes from different passages of BMSCs shows that the proteins involved in TGF-ß signaling pathway are regulated in abundance, which could be markers for the therapeutic ability of BMSC exosomes. Collectively, the data presented by this study can be a resource for further study of exosome research.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , MicroARNs , Ratas , Humanos , Animales , Exosomas/metabolismo , Proteómica , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical/metabolismo , Células de la Médula Ósea/metabolismo , MicroARNs/metabolismo
6.
Mol Biol Evol ; 39(11)2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36260528

RESUMEN

Cytonuclear coordination between biparental-nuclear genomes and uniparental-cytoplasmic organellar genomes in plants is often resolved by genetic and transcriptional cytonuclear responses. Whether this mechanism also acts in allopolyploid members of other kingdoms is not clear. Additionally, cytonuclear coordination of interleaved allopolyploid cells/individuals within the same population is underexplored. The yeast Saccharomyces pastorianus provides the opportunity to explore cytonuclear coevolution during different growth stages and from novel dimensions. Using S. pastorianus cells from multiple growth stages in the same environment, we show that nuclear mitochondria-targeted genes have undergone both asymmetric gene conversion and growth stage-specific biased expression favoring genes from the mitochondrial genome donor (Saccharomyces eubayanus). Our results suggest that cytonuclear coordination in allopolyploid lager yeast species entails an orchestrated and compensatory genetic and transcriptional evolutionary regulatory shift. The common as well as unique properties of cytonuclear coordination underlying allopolyploidy between unicellular yeasts and higher plants offers novel insights into mechanisms of cytonuclear evolution associated with allopolyploid speciation.


Asunto(s)
Cerveza , Conversión Génica , Genoma , Núcleo Celular/genética
7.
BMC Med ; 21(1): 173, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147645

RESUMEN

BACKGROUND: Apatinib, a highly selective VEGFR2 inhibitor, significantly improved efficacy versus placebo as a third- and later-line treatment for advanced gastric cancer in phase 2 and 3 trials. This prospective, single-arm, multicenter phase IV AHEAD study was conducted to verify the safety and efficacy of apatinib in patients with advanced or metastatic gastric or gastroesophageal adenocarcinoma after at least two lines of systematic therapy in clinical practice settings. METHODS: Patients with advanced gastric cancer who had previously failed at least two lines of chemotherapy received oral apatinib until disease progression, death or unacceptable toxicity. The primary endpoint was safety. The secondary endpoints included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS). Adverse events were summarized by the incidence rate. Median OS and PFS were estimated using the Kaplan-Meier method. ORR, DCR, OS at 3 and 6 months, and PFS at 3 and 6 months were calculated, and their 95% CIs were estimated according to the Clopper-Pearson method. RESULTS: Between May 2015 and November 2019, a total of 2004 patients were enrolled, and 1999 patients who received at least one dose of apatinib were assessed for safety. In the safety population, 87.9% of patients experienced treatment-related adverse events (TRAEs), with the most common hypertension (45.2%), proteinuria (26.5%), and white blood cell count decreased (25.3%). Additionally, 51% of patients experienced grade ≥ 3 TRAEs. Fatal TRAEs occurred in 57 (2.9%) patients. No new safety concerns were reported. Among the 2004 patients included in the intention-to-treat population, the ORR was 4.4% (95% CI, 3.6-5.4%), and DCR was 35.8% (95% CI, 33.7-38.0%). The median PFS was 2.7 months (95% CI 2.2-2.8), and the median OS was 5.8 months (95% CI 5.4-6.1). CONCLUSIONS: The findings in the AHEAD study confirmed the acceptable and manageable safety profile and clinical benefit of apatinib in patients with advanced gastric cancer as a third- or later-line of treatment. TRIAL REGISTRATION: This study was registered with ClinicalTrials.gov NCT02426034. Registration date was April 24, 2015.


Asunto(s)
Adenocarcinoma , Antineoplásicos , Neoplasias Gástricas , Humanos , Antineoplásicos/efectos adversos , Neoplasias Gástricas/tratamiento farmacológico , Estudios Prospectivos , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Unión Esofagogástrica/patología
8.
Electrophoresis ; 44(15-16): 1210-1219, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37075199

RESUMEN

Wear debris analysis provides an early warning of mechanical transmission system aging and wear fault diagnosis, which has been widely used in machine health monitoring. The ability to detect and distinguish the ferromagnetic and nonmagnetic debris in oil is becoming an effective way to assess the health status of machinery. In this work, an Fe-poly(dimethylsiloxane) (PDMS)-based magnetophoretic method for the continuous separation of ferromagnetic iron particles by diameter and the isolation of ferromagnetic particles and nonmagnetic particles with similar diameter by type is developed. The particles experience magnetophoretic effects when passing through the vicinity of the Fe-PDMS where the strongest gradient of the magnetic fields exists. By choosing a relatively short distance between the magnet and the sidewall of the horizontal main channel and the length of Fe-PDMS with controlled particles flow rate, the diameter-dependent separation of ferromagnetic iron particles, that is, smaller than 7 µm, in the range of 8-12 µm, and larger than 14 µm, and the isolation of ferromagnetic iron particles and nonmagnetic aluminum particles based on opposite magnetophoretic behaviors by types are demonstrated, providing a potential method for the detection of wear debris particles with a high sensitivity and resolution and the diagnostic of mechanical system.


Asunto(s)
Imanes , Microfluídica , Hierro
9.
Cell Biol Int ; 47(6): 1126-1135, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36841942

RESUMEN

Diabetic nephropathy (DN) is one of the most common complications of diabetes. Gradual loss of podocytes is a sign of DN and pyroptosis mechanistically correlates with podocyte injury in DN; however, the mechanism(s) involved remain unknown. Here we reveal that TRIM29 is overexpressed in high glucose (HG)-treated murine podocytes cells and that TRIM29 silencing significantly inhibits podocyte damage due to HG treatment, as evidenced by lower desmin expression and greater nephrin expression. Additionally, flow cytometry analysis showed that TRIM29 silencing significantly inhibited HG treatment-induced pyroptosis, which was confirmed by immunoblotting for NLRP3, active Caspase-1, GSDMD-N, and phosphorylated NF-κB-p65. Conversely, overexpression of TRIM29 could trigger pyroptosis that was attenuated by NF-κB inhibition, indicating that TRIM29 promotes pyroptosis through the NF-κB pathway. Mechanistic studies revealed that TRIM29 interacts with IκBα to mediate its ubiquitination-dependent degradation, which in turn leads to NF-κB activation. Taken together, our data demonstrate that TRIM29 can promote podocyte pyroptosis by activating the NF-κB/NLRP3 pathway. Thus, TRIM29 represents a potentially novel therapeutic target that may also be clinically relevant in the management of DN.


Asunto(s)
Nefropatías Diabéticas , Podocitos , Animales , Ratones , Nefropatías Diabéticas/metabolismo , Proteínas de Unión al ADN/metabolismo , Inflamasomas/metabolismo , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Podocitos/metabolismo , Piroptosis , Factores de Transcripción/metabolismo
10.
Analyst ; 148(24): 6350-6358, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37966221

RESUMEN

This article proposes a film-linked electrostatic self-assembly microfluidic chip for the first time, designed to be ready-to-use. Barrier films are used to isolate the gas/liquid path microchannels and the pre-stored reagents of the chip before use. Through the linkage design between the film materials, the motion of barrier films is linked to the structural changes inside the chip. Under the combined action of the rebound force of the elastic substrate, the electrostatic adsorption force between the substrates, and the reaction force of the elastic film, the elastic substrate and the liquid storage substrate are instantly bonded, and the self-assembly of the chip is completed within 1 s. By using six independently output programmable sequences to perform the sequential quantitative pumping of pre-stored reagents, the transfer and mixing of samples and pre-stored reagents are automatically driven in a confined space, which greatly reduces the contamination risk and loss rate of samples/reagents, and improves the accuracy and reproducibility of test results. In addition, the microfluidic multi-step reaction driven in parallel can avoid liquid reflux, accurately control the amount of reactant transfer, and realize the quantitative detection of samples. Multiple reactions can be performed synchronously without interference, saving the test time. Since each gas path is independently controllable, the chip can be extended to a variety of biochemical reactions and has the potential to detect a variety of substances.

11.
J Chem Phys ; 158(10): 104303, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36922128

RESUMEN

The trade-off of stiffness and ductility of metals has long plagued materials scientists. To address this issue, atomic structure designs of short-range ordering (SRO) to sub-nanometer and nanometer scales have received much interest in tailoring the atomic environment and electronic interaction between solute and solvent atoms. Taking an example of Al-Li alloy with high specific stiffness and reverse correlation of Young's modulus and melting point, in this work, we investigate the SRO-dependent stiffness and intrinsic ductile-brittle properties by performing a full-configuration strategy containing various structural ordering features. It suggests that the short-range ordered arrangement of Li atoms can effectively enhance the stiffness while keeping ductility, playing a hydrostatic pressure-like role. Our findings present fundamental knowledge to enable high stiffness and ductility for solvent phases with low modulus through designing local short-range ordered cluster structures.

12.
Appl Opt ; 62(4): 1082-1087, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36821166

RESUMEN

Diffractive deep neural networks (D2NNs) have demonstrated their importance in performing various all-optical machine learning tasks such as classification and segmentation. However, current D2NNs can only detect spatial domain intensity information. They cannot solve problems that rely on frequency information, such as laser linewidth compression. We propose a new D2NN architecture that fully exploits frequency domain information. We demonstrate that only frequency domain D2NN (OF-D3NN) can be trained using deep learning algorithms and be successfully integrated into a free-space optical communications system (FSO) for information recovery.

13.
J Environ Manage ; 345: 118802, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37591094

RESUMEN

Microplastics refer to plastic particles measuring less than 5 mm, which has led to serious environmental problem and the detection of these tiny particles is crucial for understanding the corresponding distribution and impact on the marine environment. In this paper, an improved faster region-based convolutional neural network (R-CNN) model was developed for the identification and detection of microplastic particles. In the proposed model, the residual network-50 (ResNet-50) is employed as the backbone with the replacement of the traditional one to enhance the feature extraction capability and the feature pyramid networks (FPN) module is introduced together for solving the multi-scale target detection. By using the improved Faster R-CNN model, the network model performance is enhanced where the average confidence of detecting unique microplastic particles in the marine environment reaches as high as 99%. Moreover, the microparticles mixture was bounded precisely via the predicted bounding boxes without missing detection and wrong detection. In this way, the successful identification of polystyrene microplastic particles from the particles suspension with similar shapes but various conditions of backgrounds, brightness, distributions and object sizes, was achieved by employing the proposed improved Faster R-CNN model, enabling the accurate detection of microplastic particles in marine environment.


Asunto(s)
Microplásticos , Plásticos , Redes Neurales de la Computación , Poliestirenos
14.
BMC Med ; 20(1): 472, 2022 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-36482345

RESUMEN

BACKGROUND: Anlotinib, a tyrosine kinase inhibitor, has shown encouraging anti-tumor activity in esophageal squamous cell carcinoma (ESCC). This study was designed to assess the efficacy and safety of anlotinib plus paclitaxel and cisplatin (TP) as first-line therapy for advanced ESCC. METHODS: In a multi-center, single-arm, phase II clinical trial, patients (aged > 18 years) with ESCC, which was judged to be locally advanced, recurrent, or metastatic, received 10 mg oral anlotinib once daily on days 1-14, 135 mg/m2 intravenous paclitaxel on day 1, and 60-75 mg/m2 intravenous cisplatin on days 1-3 every 3 weeks for a maximum of 4-6 cycles as the initial therapy in five centers in China. Subsequently, patients received anlotinib monotherapy (10 mg) as maintenance therapy until tumor progression or intolerable toxicity. The primary endpoint was progression-free survival (PFS). RESULTS: Forty-seven patients were enrolled in this study between October 2019 and March 2021. The median follow-up was 14.04 months (IQR, 9.30-19.38). Of 46 with assessable efficacy, the median PFS and median overall survival were 8.38 months (95% CI, 6.59-10.17) and 18.53 months (95% CI, 13.11-23.95), respectively. The objective response rate was 76.1% (95% CI, 61.2-87.4%), with 4 (8.7%) complete responses and 31 (67.4%) partial responses. The disease control rate was 91.3% (95% CI, 79.2-97.6%). The median duration of response was 6.80 months (95% CI, 4.52-9.08), and 1 patient had an ongoing response for 23 months. Subgroup analysis revealed no association between clinical factors and survival or response. Of the 47 patients with assessable safety, the main grade ≥ 3 treatment-emergent adverse events (TEAEs) were neutropenia (17.0%), bone marrow suppression (12.8%), and vomiting (10.6%). No treatment-related deaths or serious TEAEs were observed. Notably, higher c-Kit levels were an independent factor for superior PFS (HR = 0.032; 95% CI, 0.002-0.606; P = 0.022). CONCLUSIONS: The study demonstrated a manageable safety profile and durable clinical response of anlotinib plus TP as first-line therapy in advanced ESCC, which suggested a potential therapeutic option for this population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04063683. Registered 21 August 2019.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Paclitaxel/efectos adversos , Cisplatino/efectos adversos , Neoplasias Esofágicas/tratamiento farmacológico , China
15.
Opt Express ; 30(14): 24394-24406, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-36236995

RESUMEN

Single image dehazing is a challenging task because of the hue and brightness distortion problems due to the atmospheric scattering. These problems limit the perceptual fidelity, as well as information integrity, of a given image. In this paper, we propose an image dehazing method based on the optical neural networks dehazing by simulating optical diffraction. The algorithm is trained from a large number of hazy images and their corresponding clean images. The experimental results demonstrate that the proposed method has reached an advanced level in both PSNR and SSIM dehazing performance indicators, and the amount of calculation is less than most artificial neural networks.

16.
Exp Cell Res ; 408(2): 112863, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34626587

RESUMEN

Forkhead box M1 (FOXM1) has been reported to play a protective role against acute kidney injury by driving tubular regeneration. This study aims to probe the function of FOXM1 in diabetic nephropathy (DN) and the molecules involved. FOXM1 was poorly expressed in DN-diseased kidney tissues. A murine model of DN was established, and podocytes cells (MPC5) were treated with high-glucose (HG) for in vitro studies. FOXM1 overexpression improved kidney function and reduced pathological changes in mice, and it increased the expression of the podocyte marker Nephrin in kidney tissues. In vitro, FOXM1 increased viability and reduced pyroptosis of the HG-treated MPC5 cells, and it elevated the expression of the podocyte marker Nephrin whereas reduced the expression of pyroptosis-related NLRP3 inflammasome and cleaved caspase 1. FOXM1 bound to the promoter of sirtuin 4 (SIRT4) to induce transcriptional activation. Downregulation of SIRT4 blocked the protective roles of FOXM1 both in vivo and in vitro. Phosphorylation of nuclear factor-kappa B (NF-κB) in HG-treated cells was suppressed by FOXM1 but restored after SIRT4 inhibition. In conclusion, this study suggested that FOXM1 transcriptionally activates SIRT4 and inhibits NF-κB signaling and the NLRP3 inflammasome to alleviate kidney injury and podocyte pyroptosis in DN.


Asunto(s)
Lesión Renal Aguda/genética , Nefropatías Diabéticas/genética , Proteína Forkhead Box M1/genética , Proteínas Mitocondriales/genética , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Sirtuinas/genética , Lesión Renal Aguda/patología , Animales , Nefropatías Diabéticas/patología , Regulación de la Expresión Génica/genética , Humanos , Inflamasomas/genética , Riñón/lesiones , Riñón/metabolismo , Riñón/patología , Ratones , FN-kappa B/genética , Podocitos/metabolismo , Podocitos/patología , Piroptosis/genética , Transducción de Señal
17.
Appl Opt ; 61(26): 7748-7756, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-36256377

RESUMEN

Research on the polarization reflection distribution characteristics of wakes on the sea surface can provide a theoretical basis for ocean wake target detection and has important research value in the field of ship and underwater moving target monitoring. The Kelvin wake model and the Cox-Munk model are used to describe a wake on a rough sea surface. Considering the atmospheric Rayleigh scattering and the reflection characteristics of a rough sea surface, a visible spectrum band wake polarization characteristic model based on the Stokes vector and Mueller matrix is established to explore the polarization reflection distribution characteristics of wakes on the sea surface under skylight background at different wind speeds, wind directions, and sun angles. A simulation is done of the airborne polarization reflection imaging of wakes on a rough sea surface. The results show that under the determined observation angle, the polarization distribution characteristics of wakes on a rough sea surface are mainly related to the angle of the sun. The polarization contrast of simulated wakes in typical scenes is acceptable, and it is feasible to detect sea wake targets by the polarization method. The analysis and simulation of the wake polarization characteristics model can provide a theoretical basis for ocean wake target detection.

18.
Planta ; 253(1): 8, 2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33387047

RESUMEN

MAIN CONCLUSION: The molecular mechanism underlying white petal color in Brassica napus was revealed by transcriptomic and metabolomic analyses. Rapeseed (Brassica napus L.) is one of the most important oilseed crops worldwide, but the mechanisms underlying flower color in this crop are known less. Here, we performed metabolomic and transcriptomic analyses of the yellow-flowered rapeseed cultivar 'Zhongshuang 11' (ZS11) and the white-flowered inbred line 'White Petal' (WP). The total carotenoid contents were 1.778-fold and 1.969-fold higher in ZS11 vs. WP petals at stages S2 and S4, respectively. Our findings suggest that white petal color in WP flowers is primarily due to decreased lutein and zeaxanthin contents. Transcriptome analysis revealed 10,116 differentially expressed genes with a fourfold or greater change in expression (P-value less than 0.001) in WP vs. ZS11 petals, including 1,209 genes that were differentially expressed at four different stages and 20 genes in the carotenoid metabolism pathway. BnNCED4b, encoding a protein involved in carotenoid degradation, was expressed at abnormally high levels in WP petals, suggesting it might play a key role in white petal formation. The results of qRT-PCR were consistent with the transcriptome data. The results of this study provide important insights into the molecular mechanisms of the carotenoid metabolic pathway in rapeseed petals, and the candidate genes identified in this study provide a resource for the creation of new B. napus germplasms with different petal colors.


Asunto(s)
Brassica napus , Carotenoides , Flores , Metaboloma , Pigmentación , Transcriptoma , Brassica napus/genética , Carotenoides/metabolismo , Flores/genética , Regulación de la Expresión Génica de las Plantas , Metaboloma/genética , Pigmentación/genética , Transcriptoma/genética
19.
J Transl Med ; 19(1): 411, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34579742

RESUMEN

BACKGROUND: Peritoneal dialysis (PD) is a form of dialysis to replace the function of kidney, that uses the peritoneum as a dialysis membrane to remove metabolites and water retained in the body. Vitamin D deficiency is prevalent in patients treated with PD. This research investigated the correlation between serum 25-hydroxyvitamin D [25(OH)D] concentration and anemia, microinflammation, and oxidative stress in PD patients. METHODS: 62 PD patients and 56 healthy volunteers were recruited in this research. Serum concentrations of 25(OH)D and basic parameters of anemia were detected. The correlation between serum 25(OH)D concentration with anemia, oxidative stress, and microinflammatory state were analyzed. RESULTS: In the PD group, the concentration of 25(OH)D was lower than the healthy control (HC) group (p < 0.001). Hemoglobin, red blood cell count (RBC), and total iron binding capacity (TIBC) in the PD group was significantly lower (all p < 0.001), while high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α) concentrations were significantly higher, than the HC group (all p < 0.001). In the PD group, malondialdehyde (MDA) concentration was higher than in the HC group (p < 0.001), while superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were lower (both p < 0.001). Serum 25(OH)D exhibited positive correlation with hemoglobin (r = 0.4509, p = 0.0002), RBC (r = 0.3712, p = 0.0030), TIBC (r = 0.4700, p = 0.0001), SOD (r = 0.4992, p < 0.0001) and GSH-Px (r = 0.4312, p = 0.0005), and negative correlation with hs-CRP (r = - 0.4040, p = 0.0011), TNF-α (r = - 0.4721, p = 0.0001), IL-6 (r = - 0.5378, p < 0.0001) and MDA (r = - 0.3056, p = 0.0157). CONCLUSION: In conclusion, reduced serum 25(OH)D concentrations in PD patients contribute to anemia, oxidative stress and microinflammatory state.


Asunto(s)
Anemia , Diálisis Peritoneal , Anemia/complicaciones , Humanos , Malondialdehído , Estrés Oxidativo , Vitamina D
20.
Phys Chem Chem Phys ; 23(47): 26887-26901, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34825680

RESUMEN

The poor corrosion resistance of Mg alloys is a major challenge for their applications. The corrosion of Mg alloys is mainly controlled by the anodic dissolution of Mg and the cathodic hydrogen evolution reaction (HER), which is closely related to the stability and the hydrogen adsorption of the Mg surface. In this work, the effects of alloying elements (As, Ge, Cd, Zn, Ga, Al, and Y) on the stability and the hydrogen adsorption of a Mg(0001) surface have been studied based on first principles calculations. We have developed a horizontally integrated approach to evaluate their effects on corrosion resistance using parameters such as the surface energy, vacancy formation energy, Bader charge, electron density distribution, and the adsorption free energy of H atom at different adsorbed sites. We found that the doped atoms could significantly change the surface atomic structure and electron transfer on the Mg surface. These behaviors modified the energy required to detach the nearest neighbors of doped atoms from the Mg surface, the adsorption free energy of H atoms, and the stable adsorption sites of H atoms on the Mg surface, which regulate the corrosion resistance of Mg alloys. Interestingly, we found that Y doping on the Mg surface increased the corrosion resistance and our new method had tremendous potential in the rapid screening of alloying elements that could improve the stability of Mg alloys and inhibit the hydrogen evolution reaction.

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