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1.
Heliyon ; 10(12): e33297, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39021992

RESUMEN

This study aims to enhance the precision of analyzing athlete behavior characteristics, thereby optimizing sports training and competitive strategies. This study introduces an innovative Ant Colony Optimization (ACO) clustering model designed to address the high-dimensional clustering issues in athlete behavior data by simulating the path selection mechanism of ants searching for food. The development process of this model includes fine-tuning ACO parameters, optimizing for features specific to sports data, and comparing it with traditional clustering algorithms, and similar research models based on the neural network, support vector machines, and deep learning. The results indicate that the ACO model significantly outperforms the comparison algorithms in terms of silhouette coefficient (0.72) and Davies-Bouldin index (1.05), demonstrating higher clustering effectiveness and model stability. Particularly noteworthy is the recall rate (0.82), a key performance indicator, where the ACO model accurately captures different behavioral characteristics of athletes, validating its effectiveness and reliability in athlete behavior analysis. The innovation lies not only in the application of the ACO algorithm to address practical issues in the field of sports but also in showcasing the advantages of the ACO algorithm in handling complex, high-dimensional sports data. However, its generality and efficiency on a larger scale or different types of sports data still need further validation. In conclusion, through the introduction and optimization of the ACO clustering model, this study provides a novel and effective approach for a deeper understanding and analysis of athlete behavior characteristics. This study holds significant importance in advancing sports science research and practical applications.

2.
bioRxiv ; 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39026742

RESUMEN

Haploinsufficiency for GATA6 is associated with congenital heart disease (CHD) with variable comorbidity of pancreatic or diaphragm defects, although the etiology of disease is not well understood. Here, we used cardiac directed differentiation from human embryonic stem cells (hESCs) as a platform to study GATA6 function during early cardiogenesis. GATA6 loss-of-function hESCs had a profound impairment in cardiac progenitor cell (CPC) specification and cardiomyocyte (CM) generation due to early defects during the mesendoderm and lateral mesoderm patterning stages. Profiling by RNA-seq and CUT&RUN identified genes of the WNT and BMP programs regulated by GATA6 during early mesoderm patterning. Furthermore, interactome analysis detected GATA6 binding with developmental transcription factors and chromatin remodelers suggesting cooperative regulation of cardiac lineage gene accessibility. We show that modulating WNT and BMP inputs during the first 48 hours of cardiac differentiation is sufficient to partially rescue CPC and CM defects in GATA6 heterozygous and homozygous mutant hESCs. This study provides evidence of the regulatory functions for GATA6 directing human precardiac mesoderm patterning during the earliest stages of cardiogenesis to further our understanding of haploinsufficiency causing CHD and the co-occurrence of cardiac and other organ defects caused by human GATA6 mutations.

3.
Int J Biol Macromol ; 273(Pt 2): 133110, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38876230

RESUMEN

In food packaging, sodium lignosulfonate nanoparticles (SLS NPs) showed significant antibacterial properties, antioxidant and UV barrier activities. Herein, the SLS NPs were synthesized via a sustainable green method and were added into egg albumin/sodium alginate mixture (EA/SA) to fabricate a safe, edible EA/SA/SNPs food packaging. A composite film EA/SA/SNP was examined microstructurally and physicochemically. The mechanical characteristics, UV protection, water resistance, and the composite film's thermal stability were all enhanced by the inclusion of SLS NPs, and water vapor permeability reduced by 44 %. This composite film exhibited robust antioxidative properties with DPPH and ABTS free radical scavenging rates reaching 76.84 % and 92.56 %, and effective antimicrobial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with antibacterial rates reaching 98.25 % and 97.13 % for the positively charged nanoparticles interacting with the cell membrane. Freshness tests showed that the EA/SA/SNPs packaging film could delay the quality deterioration of fresh tomatoes. This composite film can slow down spoilage bacteria proliferation and prolongs food's preservation period by eight days at ambient temperature.


Asunto(s)
Alginatos , Antibacterianos , Antioxidantes , Embalaje de Alimentos , Lignina , Nanopartículas , Alginatos/química , Alginatos/farmacología , Embalaje de Alimentos/métodos , Nanopartículas/química , Antioxidantes/farmacología , Antioxidantes/química , Antibacterianos/farmacología , Antibacterianos/química , Lignina/química , Lignina/análogos & derivados , Lignina/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Permeabilidad , Vapor
4.
Int J Biol Macromol ; 274(Pt 2): 133172, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38880458

RESUMEN

In the field of bone tissue repair, the treatment of bone defects has always posed a significant challenge. In recent years, the advancement of bone tissue engineering and regenerative medicine has sparked great interest in the development of innovative bone grafting materials. In this study, a novel hydroxyapatite (HA) material was successfully prepared and comprehensively characterized. Antimicrobial experiments and biological evaluations were conducted to determine its efficacy. Based on the aforementioned research findings, 3D printing technology was employed to fabricate HA/chitosan (CS)/ polycaprolactone (PCL) scaffolds. The composition of the scaffold materials was confirmed through X-ray diffractometer (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) tests, while the influence of different HA ratios on the scaffold surface morphology was observed. Additionally, antimicrobial experiments demonstrated the favorable antimicrobial activity of the scaffolds containing 30%HA + 5%CS + PCL. Furthermore, the water contact angle measurements confirmed the superhydrophilicity of the scaffolds. Finally, the excellent bioactivity and ability to promote tissue regeneration of the scaffolds were further confirmed by in vitro and in vivo experiments. This study provides new options for future repair and regeneration of bone tissue and clinical applications.

5.
Int J Biol Macromol ; 271(Pt 2): 132506, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38772466

RESUMEN

Hydrogels incorporating natural biopolymer and adhesive substances have extensively been used to develop bioactive drugs and to design cells encapsulating sturdy structure for biomedical applications. However, the conjugation of the adhesive in most hydrogels is insufficient to maintain long-lasting biocompatibility inadequate to accelerate internal organ tissue repair in the essential native cellular microenvironment. The current work elaborates the synthesis of charged choline-catechol ionic liquid (BIL) adhesive and a hydrogel with an electronegative atom rich polyphenol (PU)-laden gelatinmethacryloyl (GelMA) to improve the structural bioactivities for in vivo tracheal repair by inducing swift crosslinking along with durable mechanical and tissue adhesive properties. It was observed that bioactive BIL and PU exhibited potent antioxidant (IC 50 % of 7.91 µg/mL and 24.55 µg/mL) and antibacterial activity against E. coli, P. aeruginosa and S. aureus. The novel integration of photocurable GelMA-BIL-PU revealed outstanding mechanical strength, biodegradability and sustained drug release. The in vitro study showed exceptional cell migration and proliferation in HBECs, while in vivo investigation of the GelMA-BIL-PU hydrogel on a rat's tracheal model revealed remarkable tracheal reconstruction, concurrently reducing tissue inflammation. Furthermore, the optimized GelMA-BIL-PU injectable adhesive bioink blend demonstrated superior MSCs migration and proliferation, which could be a strong candidate for developing stem cell-rich biomaterials to address multiple organ defects.


Asunto(s)
Gelatina , Hidrogeles , Células Madre Mesenquimatosas , Metacrilatos , Polifenoles , Tráquea , Tráquea/efectos de los fármacos , Gelatina/química , Polifenoles/farmacología , Polifenoles/química , Animales , Ratas , Metacrilatos/química , Metacrilatos/farmacología , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Hidrogeles/química , Hidrogeles/farmacología , Regeneración/efectos de los fármacos , Humanos , Antibacterianos/farmacología , Antibacterianos/química , Proliferación Celular/efectos de los fármacos , Antioxidantes/farmacología , Antioxidantes/química , Movimiento Celular/efectos de los fármacos , Adhesivos Tisulares/química , Adhesivos Tisulares/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología
6.
Int J Biol Macromol ; 270(Pt 1): 132233, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38735617

RESUMEN

To reduce food-borne bacterial infection caused by food spoilage, developing highly efficient food packing film is still an urgent need for food preservation. Herein, microwave-assisted antibacterial nanocomposite films CaO2@PVP/EA/CMC-Na (CP/EC) were synthesized using waste eggshell as precursor, egg albumen (EA) and sodium carboxymethylcellulose (CMCNa) as matrix by casting method. The size of CaO2@PVP (CP) nanoparticles with monodisperse spherical structures was 100-240 nm. When microwave and CP nanoparticles (0.05 mg/mL) were treated for 5 min, the mortality of E. coli and S. aureus could reach >97 %. Under microwave irradiation (6 min), the bactericidal rate of 2.5 % CP/EC film against E. coli and S. aureus reached 98.6 % and 97.2 %, respectively. After adding CP nanoparticles, the highest tensile strength (TS) and elongation at break (EB) of CP/EC film reached 19.59 MPa and 583.43 %, respectively. At 18 °C, the proliferation of bacterial colonies on meat can be significantly inhibited by 2.5 % CP/EC film. Detailed characterization showed that the excellent meat preservation activity was due to the synergistic effect of dynamic effect generated by ROS and thermal effect of microwave. This study provides a promising approach for the packaging application of polysaccharide- and protein-based biomass nanocomposite antibacterial edible films.


Asunto(s)
Antibacterianos , Películas Comestibles , Escherichia coli , Conservación de Alimentos , Carne , Microondas , Polisacáridos , Staphylococcus aureus , Polisacáridos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Conservación de Alimentos/métodos , Carne/microbiología , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Embalaje de Alimentos/métodos , Animales , Nanocompuestos/química , Carboximetilcelulosa de Sodio/química , Nanopartículas/química , Proteínas/química , Resistencia a la Tracción
7.
Diabetes ; 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38775784

RESUMEN

Mouse models are extensively utilized in metabolic studies. However, inherent differences between the species, notably their blood glucose levels, hampered data translation into clinical settings. In this study, we confirmed GLUT1 to be the predominantly expressed glucose transporter in both adult and fetal human ß cells. In comparison, GLUT2 is detected in a small yet significant subpopulation of adult ß cells and is expressed to a greater extent in fetal ß cells. Notably, GLUT1/2 expression in INS+ cells from human stem cell-derived islet-like clusters (SC-islets) exhibited a closer resemblance to that observed in fetal islets. Transplantation of primary human islets or SC-islets, but not murine islets, lowered murine blood glucose to the human glycemic range, emphasizing the critical role of ß cells in establishing species-specific glycemia. We further demonstrate the functional requirements of GLUT1 and GLUT2 in glucose uptake and insulin secretion through chemically inhibiting GLUT1 in primary islets and SCislets, and genetically disrupting GLUT2 in SC-islets. Finally, we developed a mathematical model to predict changes in glucose uptake and insulin secretion as a function of GLUT1/2 expression. Collectively, our findings illustrate the crucial roles of GLUTs in human ß cells, and identify them as key components in establishing species-specific glycemic setpoints.

8.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 123926, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38471308

RESUMEN

Inspired by the distinguished photochemical characteristics of new organic molecule containing the chalcogenide substitution that could be potentially applied across various disciplines, in this work, the effects of atomic electronegativity of chalcogen (O, S and Se) on hydrogen bond interactions and proton transfer (PT) reaction. We present the characteristic 2,8-diphenyl-3,7-dihydroxy-4H,6H-pyrano[3,2-g]-chromene-4,6-dione (D3HF), which is based on 3-hydroxyflavone (3HF) and contains intramolecular double hydrogen bonds that is the main objective of this study to explore in detail the influence of the change of atomic electronegativity on the dual hydrogen bond interaction and the excited state proton transfer (ESPT) behavior by photoexcitation. By comparing the structural changes and infrared (IR) vibrational spectra of the D3HF derivatives (D3HF-O, D3HF-S and D3HF-Se) fluorophores in S0 and S1 states, combined with the preliminary detection of hydrogen bond interaction by core-valence bifurcation (CVB) index, we can conclude that the hydrogen bond is strengthened in S1 state, which is favorable for the occurrence of ESPT reactions. The charge recombination behavior of hydrogen bond induced by photoexcitation also further illustrates this point. Via constructing potential energy surfaces (PESs) based on restrictive optimization, we finally clarify the excited state single PT mechanism for D3HF derivatives. Specially, we confirm change of atomic electronegativity has a regulatory effect on the ESIPT behavior of D3HF and its derivatives, that is, the lower the atomic electronegativity is more conducive to the ESIPT reaction.

9.
Int J Med Robot ; 20(1): e2617, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38536731

RESUMEN

BACKGROUND: Controlling a multi-grasp prosthetic hand still remains a challenge. This study explores the influence of merging gaze movements and augmented reality in bionics on improving prosthetic hand control. METHODS: A control system based on gaze movements, augmented reality, and myoelectric signals (i-MYO) was proposed. In the i-MYO, the GazeButton was introduced into the controller to detect the grasp-type intention from the eye-tracking signals, and the proportional velocity scheme based on the i-MYO was used to control hand movement. RESULTS: The able-bodied subjects with no prior training successfully transferred objects in 91.6% of the cases and switched the optimal grasp types in 97.5%. The patient could successfully trigger the EMG to control the hand holding the objects in 98.7% of trials in around 3.2 s and spend around 1.3 s switching the optimal grasp types in 99.2% of trials. CONCLUSIONS: Merging gaze movements and augmented reality in bionics can widen the control bandwidth of prosthetic hand. With the help of i-MYO, the subjects can control a prosthetic hand using six grasp types if they can manipulate two muscle signals and gaze movement.


Asunto(s)
Miembros Artificiales , Realidad Aumentada , Humanos , Electromiografía , Diseño de Prótesis , Mano/fisiología , Movimiento , Fuerza de la Mano/fisiología
10.
Molecules ; 29(2)2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38257373

RESUMEN

The impact of the chalcogen atomic electronegativity (O, S, and Se atoms) of new organic molecules on excited-state dynamical reactions is self-evident. Inspired by this kind of distinguished photochemical characteristic, in this work, we performed a computational investigation of chalcogen-substituted 3,6-bis(4,5-dihydroxyoxazo-2-yl)benzene-1,2-diol (BDYBD) derivatives (i.e., BDYBD-O, BDYBD-S, and BDYBD-Se). In this paper, we pay close attention to characteristic BDYBD derivatives that contain intramolecular double hydrogen bonds (O1-H2···N3 and O4-H5···N6). The main goal of this study was to explore how changes in atomic electronegativity affect the way hydrogen bonds interact and how excited molecules affect transfer protons. We go into further detail in the main text of the paper. By fixing our attention to geometrical variations and infrared (IR) vibrational spectra between the S0 and S1 states, exploring hydrogen bonding behaviors using the core-valence bifurcation (CVB) index, and simulating hydrogen bonding energy (EHB) via the atom in molecule (AIM) method, we clarified the photo-induced strengthened dual hydrogen bonding interactions that facilitate the excited-state dual-proton transfer (ESDPT) behavior of BDYBD derivatives. The reorganization of charge stemming from photoexcitation further verifies the tendencies of ESDPT reactions. We relied on constructing potential energy surfaces (PESs) by adopting a restrictive optimization approach, and herein, we finally clarify the gradual ESDPT mechanism of BDYBD derivatives. Particularly, we confirm that the variation in chalcogen atomic electronegativity has a regulatory effect on the ESDPT behavior of BDYBD derivatives; that is, the lower the atomic electronegativity, the more favorable it is for the gradual ESDPT reaction.

11.
Reprod Domest Anim ; 59(1): e14512, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38069628

RESUMEN

Lambda light chains (λ-LCs) are frequently responsible for triggering the activation of inflammatory factors in autoimmune disorders, and an increase in their levels will cause various pathological changes in serum. The aim of this study was to determine the histological differences between the epididymis and testis of normal and cryptorchid Bactrian camels and the differences in λ-LC expression in the epididymis and testis of normal and cryptorchid Bactrian camels. Haematoxylin and eosin (H&E) staining was used to examine the pathological changes in cryptorchidism. The gene and protein levels of λ-LC were determined using RT-qPCR and western blot. The distribution of λ-LCs was assessed by immunohistochemistry and immunofluorescence. Compared with that in normal Bactrian camels, the diameter of the epididymal lumen and the thickness of the epithelium were decreased in the epididymis of cryptorchidic animals. Additionally, no sperm was detected in the cavity of the cryptorchidic epididymis. Meanwhile, the expression of λ-LC was significantly increased in the cryptorchidic epididymis at both the mRNA and protein levels (p < .05). The highest protein expression of λ-LC was found in epididymal epithelial halo cells and testicular Sertoli cells. These findings suggested that the structural changes observed in the epididymal epithelium of cryptorchidic camels affect its secretory and absorptive functions. Additionally, the high level of λ-LC expression recorded in halo cells suggested that these cells play an important role in epithelial immunity in cryptorchidic Bactrian camels. Furthermore, the high λ-LC expression levels detected in normal testicular Sertoli cells indicated that λ-LCs may be involved in spermatogenesis. The results of this study provide clues for an in-depth study of immunological sterility in cryptorchidic Bactrian camels.


Asunto(s)
Criptorquidismo , Epidídimo , Masculino , Animales , Epidídimo/metabolismo , Criptorquidismo/metabolismo , Criptorquidismo/veterinaria , Camelus , Inmunoglobulinas/metabolismo
12.
bioRxiv ; 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37961332

RESUMEN

Understanding diverse responses of individual cells to the same perturbation is central to many biological and biomedical problems. Current methods, however, do not precisely quantify the strength of perturbation responses and, more importantly, reveal new biological insights from heterogeneity in responses. Here we introduce the perturbation-response score (PS), based on constrained quadratic optimization, to quantify diverse perturbation responses at a single-cell level. Applied to single-cell transcriptomes of large-scale genetic perturbation datasets (e.g., Perturb-seq), PS outperforms existing methods for quantifying partial gene perturbation responses. In addition, PS presents two major advances. First, PS enables large-scale, single-cell-resolution dosage analysis of perturbation, without the need to titrate perturbation strength. By analyzing the dose-response patterns of over 2,000 essential genes in Perturb-seq, we identify two distinct patterns, depending on whether a moderate reduction in their expression induces strong downstream expression alterations. Second, PS identifies intrinsic and extrinsic biological determinants of perturbation responses. We demonstrate the application of PS in contexts such as T cell stimulation, latent HIV-1 expression, and pancreatic cell differentiation. Notably, PS unveiled a previously unrecognized, cell-type-specific role of coiled-coil domain containing 6 (CCDC6) in guiding liver and pancreatic lineage decisions, where CCDC6 knockouts drive the endoderm cell differentiation towards liver lineage, rather than pancreatic lineage. The PS approach provides an innovative method for dose-to-function analysis and will enable new biological discoveries from single-cell perturbation datasets.

13.
Artículo en Inglés | MEDLINE | ID: mdl-38035389

RESUMEN

There is an urgent need for wearable sensors that continuously monitor human physiological conditions in real time. Herein, an ESM-PDA@rGO-based flexible wearable temperature sensor was successfully constructed by integrating an eggshell membrane (ESM) with reduced graphene oxide (rGO) through dopamine (DA) polymerization. Depending on the "bridge effect" of diversified polydopamine (PDA) chains, on the one hand, a staggered arrangement of PDA-rGO frameworks and a lot of conductive pathways were produced and acted as an active layer. On the other hand, PDA-rGO frameworks were linked with ESM by PDA chains as a flexible sensing nanofilm. As a result, these mechanical merits of the ESM-PDA@rGO exhibited a 1.8-fold increase in Young' s modulus and 1.4-fold increase in tensile strength. Thereby, the conformability and performance of the temperature sensor were greatly enhanced, showing excellent sensitivity (-2.23%/°C), good linearity (R2 = 0.979), as well as stability. Especially, the flexible sensing nanofilm is evolved from the staggered arrangement of PDA-rGO frameworks, which endows it with rapid response (only 4-8 s), high resolution (0.1 °C), as well as excellent long-term durability (10 weeks). More importantly, the temperature sensor demonstrates insensitivity to bending deformation, ensuring reliable wearing stability. The sensor allows for online, real-time monitoring of human body temperature, encompassing both core (forehead, temple, cochlea, and exhale gas) and shell (palm and back of the hand, fingertip, and instep) temperatures. Particularly, it can accurately assess minor changes in peripheral body temperature before and after exercise, and it is capable of mapping daily patterns of body temperatures. The developed temperature sensor will provide us new materials design concepts and holds considerable promise in the fields of e-skin, disease surveillance, prediction, and diagnose.

14.
PLoS One ; 18(10): e0290775, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37878614

RESUMEN

MTNR1A and MTNR1B, two high-affinity MT membrane receptors found in mammals, mediate the activity of MT on the HPGA to regulate animal reproduction. Nevertheless, the expression patterns and function of the MTNR1A and MTNR1B genes in the HPTA of seasonal estrus sheep and perennial estrus sheep have not been elucidated. We studied the expression of MTNR1A and MTNR1B in the hypothalamic-pituitary-testicular axis (HPTA) of Tibetan sheep at different reproductive stages using histochemistry, enzyme linked immunosorbent assay (ELSIA), scanning electron microscopy, transmission electron microscopy, quantitative Real-time PCR (qRT-PCR), and Western blot (WB), and analyzed the relationship between their expression and reproductive hormone receptors. We also compared relevant characteristics between seasonal Tibetan sheep and non-seasonal Small Tail Han sheep in the same pastoral area. The results showed that MTNR1A and MTNR1B were expressed in all tissues of the Tibetan sheep HPTA, and both were co-expressed in the cytoplasm of epididymis basal and halo cells located at common sites of the epididymis basement membrane, forming an immune barrier. The qRT-PCR analysis showed that not only MTNR1A but also N-acetyltransferase (AANAT), hydroxyindole-oxygen- methyltransferase (HIOMT), androgen receptor (AR), and estrogen receptor α (ERα) mRNA expression was significantly upregulated in the testis and epididymis of Tibetan sheep during the breeding season, whereas no clear upregulation of these genes was observed in the tissues of Small Tail Han sheep. MTNR1A and MTNR1B are important regulators of the HPTA in sheep. MTNR1A mediates seasonal estrus regulation in Tibetan sheep. Both MTNR1A and MTNR1B may play important roles in formation of the blood-epididymal barrier. The results of this study should help advance research on the mechanism of reproductive regulation of the HPTA in male animals and provide reference data for improving the reproductive rate of seasonal breeding animals.


Asunto(s)
Melatonina , Testículo , Femenino , Ovinos , Masculino , Animales , Testículo/metabolismo , Tibet , Receptores de Melatonina/genética , Reproducción/fisiología , Mamíferos/metabolismo
15.
Materials (Basel) ; 16(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687685

RESUMEN

1000 MPa grade low-carbon martensite press hardening steels (PHS) are widely used in energy-absorbing domains of automotive parts, such as the bottom of a B-pillar. To prevent oxide scale formation during hot forming, this PHS is often required to be protected by an additional Al-Si coating. In addition, although the low carbon martensitic microstructure grants it excellent bending toughness, the ductility tends to be limited. In this study, a novel 1000 MPa grade ultrafine-grained (UFG) martensite-ferrite (F-M) dual-phase (DP) PHS with superior oxidation resistance was designed using tailored additions of Cr, Mn, and Si, and refining the initial microstructure. Only 0.55 ± 0.18 µm thick oxide film is formed in the designed steel during austenitizing heating and stamping, which is significantly lower than the 24.6 ± 3.1 µm thick oxide film formed in conventional 1000 MPa grade low-carbon martensite PHS under the identical condition. The superior oxidation resistance of designed steel can be attributed to the rapid formation of the protective Si-rich, Cr-rich, and Mn-rich oxide layers during annealing. Moreover, due to the presence of ferrite and ultrafine microstructure, the designed steel also shows a significant improvement in ductility from 8.5% to 16.8% without sacrificing strength and bending toughness compared with conventional 1000 MPa grade low-carbon martensite PHS.

16.
Nat Genet ; 55(8): 1336-1346, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37488417

RESUMEN

Comprehensive enhancer discovery is challenging because most enhancers, especially those contributing to complex diseases, have weak effects on gene expression. Our gene regulatory network modeling identified that nonlinear enhancer gene regulation during cell state transitions can be leveraged to improve the sensitivity of enhancer discovery. Using human embryonic stem cell definitive endoderm differentiation as a dynamic transition system, we conducted a mid-transition CRISPRi-based enhancer screen. We discovered a comprehensive set of enhancers for each of the core endoderm-specifying transcription factors. Many enhancers had strong effects mid-transition but weak effects post-transition, consistent with the nonlinear temporal responses to enhancer perturbation predicted by the modeling. Integrating three-dimensional genomic information, we were able to develop a CTCF-loop-constrained Interaction Activity model that can better predict functional enhancers compared to models that rely on Hi-C-based enhancer-promoter contact frequency. Our study provides generalizable strategies for sensitive and systematic enhancer discovery in both normal and pathological cell state transitions.


Asunto(s)
Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Humanos , Elementos de Facilitación Genéticos/genética , Diferenciación Celular/genética , Factores de Transcripción/genética , Redes Reguladoras de Genes/genética , Cromatina/genética
17.
J Colloid Interface Sci ; 648: 535-550, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37307610

RESUMEN

Owing to the numerous potential applications of ZnO nanomaterials, the development of ZnO-based nanocomposites has become of great scientific interest in various fields. In this paper, we are reporting the fabrication of a series of ZnO/C nanocomposites through a simple "one-pot" calcination method under three different temperatures, 500 ℃, 600 ℃, and 700 ℃, with samples labeled as ZnO/C-500, -600, and -700, respectively. All samples exhibited adsorption capabilities and photon-activated catalytic and antibacterial properties, with the ZnO/C-700 sample showing superior performance among the three. The carbonaceous material in ZnO/C is key to expanding the optical absorption range and improving the charge separation efficiency of ZnO. The remarkable adsorption property of the ZnO/C-700 sample was demonstrated using Congo red dye, and is credited to its good hydrophilicity. It was also found to exhibit the most notable photocatalysis effect due to its high charge transfer efficiency. The hydrophilic ZnO/C-700 sample was also examined for antibacterial effects both in vitro (against Escherichia coli and Staphylococcus aureus) and in vivo (against MSRA-infected rat wound model), and it was observed to exhibit synergistic killing performance under visible-light irradiation. A possible cleaning mechanism is proposed on the basis of our experimental results. Overall, this work presents a facile way of synthesizing ZnO/C nanocomposites with outstanding adsorption, photocatalysis, and antibacterial properties for the efficient treatment of organic and bacterial contaminants in wastewater.


Asunto(s)
Nanocompuestos , Purificación del Agua , Óxido de Zinc , Animales , Ratas , Óxido de Zinc/farmacología , Adsorción , Antibacterianos/farmacología , Purificación del Agua/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Catálisis
18.
Food Chem ; 426: 136535, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37331139

RESUMEN

Antibiotic monitoring remains vital to ensure human health and safety in the environment and foods. As the most popular detection method, photoelectrochemical (PEC) sensor can achieve rapid and accurate detection of antibiotics with the advantages of high sensitivity, easy-to-preparation process, as well as high selectivity. Herein, an extremely-efficient visible-light responsible ZnO/C nanocomposite was prepared and combined with acetylene black (as an enhanced conductive matrix), and the electron migration efficiency was greatly accelerated. Meanwhile, a molecularly imprinted polymer obtained by electrical agglomeration was conjugated as a specific recognizing site for target. Furthermore, the as-prepared rMIP-PEC sensor showed a low detection limit (8.75 pmol L-1, S/N = 3) in a wide linear detection range of 0.01-1000 nmol L-1 for oxytetracycline (OTC), with excellent selectivity and long-term stability. Our work shed light on applying C-doped ZnO semiconductor and molecularly imprinted polymer as photoelectric active sensing materials for rapid and accurate analysis of antibiotics in foods and environment.


Asunto(s)
Técnicas Biosensibles , Impresión Molecular , Nanocompuestos , Oxitetraciclina , Óxido de Zinc , Humanos , Animales , Oxitetraciclina/análisis , Polímeros Impresos Molecularmente , Leche/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Antibacterianos/análisis , Límite de Detección , Impresión Molecular/métodos
19.
Int J Biol Macromol ; 245: 125482, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37348576

RESUMEN

In this study, carbon dots (CDs), cellulose nanofibers (CNF) and essential oil nanoemulsion (EON) were extracted from the aril waste of Torreya grandis following nuts production. These three nanomaterials were formulated for the preparation of a composite film to be employed for postharvest tomato storage. Visual, microscopical and physicochemical properties of the prepared nanocomposite films were analyzed at different levels of CDs and CNF for optimization purposes. The UV absorption and antioxidant capacity of gelatin film with 10 % CDs (G/10CD) were enhanced compared with gelatin (G) film, concurrent with a reduction in water barrier capacity, water contact angle (WCA) and tensile strength (TS). Compared with G/10CD film, the WCA of G film after incorporation of 10 % CDs and 3 wt% CNF (G/10CD/3CNF) was significantly increased by 14.5°at 55 s. In contrast, TS increased by 1.26 MPa, as well as the significant enhancement in water barrier capacity. The above composite film mixed with EON (G/10CD/3CNF/EON) exerted further antimicrobial effects against Escherichia coli. G/10CD/3CNF/EON coating effectively extended tomato shelf life compared with the control group. Therefore, this new eco-friendly film presents several advantages of biodegradability, sustainability as well as multifunctional properties posing it as potential packaging material for food applications.

20.
bioRxiv ; 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37205540

RESUMEN

Pluripotent stem cells are defined by both the ability to unlimitedly self-renew and differentiate to any somatic cell lineage, but understanding the mechanisms that control stem cell fitness versus the pluripotent cell identity is challenging. We performed four parallel genome-scale CRISPR-Cas9 screens to investigate the interplay between these two aspects of pluripotency. Our comparative analyses led to the discovery of genes with distinct roles in pluripotency regulation, including many mitochondrial and metabolism regulators crucial for stem cell fitness, and chromatin regulators that control stem cell identity. We further discovered a core set of factors that control both stem cell fitness and pluripotency identity, including an interconnected network of chromatin factors that safeguard pluripotency. Our unbiased and systematic screening and comparative analyses disentangle two interconnected aspects of pluripotency, provide rich datasets for exploring pluripotent cell identity versus self-renewal, and offer a valuable model for categorizing gene function in broad biological contexts.

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