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1.
Indian J Otolaryngol Head Neck Surg ; 76(1): 1410-1418, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38440649

RESUMEN

Background: Body mass index(BMI) in children appears to be associated with Otitis media with effusion(OME) in observational studies, but the causal relationship is not clear. Methods: A two-sample Mendelian randomization (MR) study was used to explore the causal relationship between childhood BMI and OME in people of European ancestry. Genome-wide association studies (GWAS) of childhood BMI were used as exposures (n = 61,111), while GWAS of OME were used as outcomes (n = 429,290). The weighted inverse variance method (IVW) was used as a baseline method to test for causality. In addition, MR-Egger, simple mode analysis, weighted median, and weighted mode were used as complementary methods.MR-PRESSO analysis, MR-Egger intercept analysis, and Cochran's Q statistical analysis were also used to detect possible directional heterogeneity and polymorphism. To assess this association, we used ratios (OR) with 95% confidence intervals (ci). All statistical analyses were performed in R. Results: We selected 22 genome-wide significant single nucleotide polymorphisms (SNPs) from GWAS as instrumental variables (IVW). the IVW approach showed evidence supporting a causal relationship between BMI and OME in children (ß = 0.265, SE = 0.113, P = 0.018). MR-Egger regression showed that targeted polymorphisms were unlikely to bias the results bias (intercept=-0.022; P = 0.488), but there was no causal relationship between BMI and OME (ß = 0.584, SE = 0.465, P = 0.224). Although the results of the IVW and MR Egger analyses were not consistent, the IVW analysis maintained higher precision, and the Cochran Q test, heterogeneity and polymorphism tests showed no heterogeneity, no directionality and no polymorphism. Conclusions: MR studies suggest that genetically predicted body mass index in childhood is associated with an increased risk of OME. Notably, given the limitations of this study, the mechanism of association between body mass index and OME in childhood needs further investigation. These results support the importance of effective management of obesity, which may reduce OME occurrence and decrease OME recurrence.

2.
Acta Otolaryngol ; 144(1): 19-22, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38315117

RESUMEN

BACKGROUND: Chronic suppurative otitis media (CSOM) is a prevalent chronic inflammatory disease globally. Current research suggests a possible association between anaemia and the development of CSOM. OBJECTIVES: The objective of this trial was to investigate the relationship between iron metabolism and chronic suppurative otitis media (CSOM) in adults aged 20-60 years. MATERIALS AND METHODS: A consecutive sampling case-control study was used. The study participants were divided into a case group (42 children diagnosed with CSOM) and a control group (42 children with normal ears). Haemoglobin (Hb), Hematocrit (Hct), mean corpuscular volume of erythrocytes (MCV), serum iron level (SI), unsaturated iron-binding capacity (UIBC), total iron-binding capacity (TIBC), transferrin (TF), ferritin (Fer) were tested in all the participants, and the results were compared with the normal ranges of the World Health Organization (WHO). The comparative analysis of cases and controls was performed using the Fisher extract test, independence t-test, or Mann-Whitney U test. p-value <.05 was considered statistically significant for correlation. RESULTS: There were 61 patients with CSOM and 61 controls included in the study. In the case group, 16 out of 61 patients (26.2%) had low ferritin levels and in the control group, 1 out of 61 patients (1.6%) had low ferritin levels (p < .001). In the case group, 6 (9.8%) of 61 patients had IDA, and in the control group, there were no patients with IDA among 61 patients (p = .027). There were significant differences in SI, UIBC, and Fer parameters between the groups. CONCLUSIONS: In adult patients, the incidence of iron deficiency was higher in CSOM patients than in controls. Iron deficiency may be considered a potential risk factor for chronic suppurative otitis media, and serum iron parameters should be evaluated in these CSOM patients and further studies should be conducted to better understand the potential link between iron deficiency and CSOM.


Asunto(s)
Deficiencias de Hierro , Otitis Media Supurativa , Niño , Adulto , Humanos , Estudios de Casos y Controles , Otitis Media Supurativa/complicaciones , Enfermedad Crónica , Ferritinas , Hierro
3.
Animals (Basel) ; 14(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38338002

RESUMEN

There have been few investigations into the health benefits and meat quality of supplementing Yangzhou geese with paper mulberry silage. One hundred and twenty 28-day-old Yangzhou geese were selected for the experiment and randomly divided into two groups: a control group (CON) and a paper mulberry silage group (PM), with six replicates in each group. The experiment lasted for a total of 6 weeks. The experiment found that compared with CON, PM had a promoting effect on the average daily weight gain of Yangzhou geese (p = 0.056). Sensory and nutritional analysis of breast muscles revealed a decrease in a* value (p < 0.05) and an increase in protein content (p < 0.05) following PM treatment. Through untargeted metabolomics analysis of breast muscle samples, it was found that 11 different metabolites, including guanidinoacetic acid and other substances, had a positive effect on amino acid metabolism and lipid antioxidant pathways of PM treatment. Overall, the strategy of feeding Yangzhou geese with paper mulberry silage is feasible, which can improve the sensory quality and nutritional value of goose meat. The experiment provides basic data for the application form of goose breeding, so exploring the impact of substances within paper mulberry on goose meat should be focused on in the future.

4.
Sci Total Environ ; 917: 170518, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38286276

RESUMEN

Microplastics (MPs) are ubiquitous environmental contaminants that have negative impacts on health and safety. The gut microbiota plays multiple roles as a newly discovered virtual metabolic organ. The objective of this study was to investigate the potential of MPs to cause liver injury by disrupting the balance of gut microbiota. The results indicated that exposure to MPs resulted in liver damage and disrupted the homeostasis of gut microbiota. MPs significantly reduced the liver organ coefficient, leading to liver cell injury and impaired function. Additionally, there was an increase in the expression of fibril-related proteins, which positively correlated with MPs concentration. Furthermore, MPs increased the relative abundances of Desulfovibrio, Clostridia, Enterorhabdus, Bacteroides, and Gemella while decreasing the abundance of Dubosoella. Different concentrations of MPs exhibited varying effects on specific bacterial groups, however, both concentrations resulted in an increase in pathogenic bacteria and a decrease in beneficial bacteria, as well as alterations in microbial structure. Moreover, MPs induced oxidative stress, inflammation, apoptosis and necrosis in liver cells. The study found that MPs disrupted gut microbiota homeostasis and activated TLR2/NF-κB/NLRP3 pathway in the liver, providing a new insight into the mechanism underlying MPs-induced liver injury. These findings serve as a warning regarding environmental pollution caused by MPs.


Asunto(s)
Microbioma Gastrointestinal , Polietileno , Animales , Ratones , FN-kappa B , Microplásticos/toxicidad , Plásticos , Receptor Toll-Like 2 , Disbiosis/inducido químicamente , Proteína con Dominio Pirina 3 de la Familia NLR , Hígado
5.
Eye Contact Lens ; 50(1): 41-47, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37934166

RESUMEN

OBJECTIVES: To develop and validate a deep learning-based model for predicting 12-month axial length (AL) elongation using baseline factors and early corneal topographic changes in children treated with orthokeratology (Ortho-K) and to investigate the association between these factors and myopia control impact. METHODS: A total of 115 patients with Ortho-K were enrolled. Influential baseline factors that have a statistically significant correlation with 12-month AL from medical records were selected using Pearson correlation coefficients. Simultaneously, the height, area, and volume of the defocus region were directly calculated from the corneal topography. Then, the prediction model was developed by combining multiple linear regression and deep neural network and evaluated in an independent group (83 patients for developing the algorithm and 32 patients for evaluation). RESULTS: Age ( r= -0.30, P <0.001), spherical equivalent refractive (SE; r =0.20, P =0.032), and sex ( r =0.19, P =0.032) were significantly correlated with the AL elongation while pupil diameter, flat k, steep k, horizontal corneal diameter (white to white), anterior chamber depth, and cell density were not ( P >0.1). The prediction model was developed using age, SE, and corneal topographic variation, and the validation of the model demonstrated its effectiveness in predicting AL elongation. CONCLUSIONS: The AL elongation was accurately predicted by the deep learning model, which effectively incorporated both baseline factors and corneal topographic variation.


Asunto(s)
Aprendizaje Profundo , Miopía , Procedimientos de Ortoqueratología , Niño , Humanos , Longitud Axial del Ojo , Miopía/terapia , Topografía de la Córnea , Refracción Ocular , Estudios Retrospectivos
6.
Aquat Toxicol ; 262: 106659, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37586228

RESUMEN

Microplastics (MPs), a new class of pollutant that threatens aquatic biodiversity, are becoming increasingly prevalent around the world. Fish growth may be severely inhibited by microplastics, resulting in severe mortality. Exposure to microplastics increases the likelihood of intestinal injuries, but the underlying mechanisms remain equivocal. The objective of this study was to investigate the potential toxic mechanisms underlying microplastic-induced intestinal injury in fish and to assist researchers in identifying novel therapeutic targets. In this study, a model of carp exposed to microplastics was established successfully. Histological observation showed that exposure to polyethylene microplastics caused damage to the intestinal mucosal surface and a significant increase in goblet cells, which aggregated on the surface of the mucosa. The mucosal layer was observed to fall off. Lymphocytes in the intestinal wall proliferated and aggregated. TUNEL staining showed that apoptosis occurred in the group exposed to microplastics. The qPCR results showed that the expression of Ferroptosis apoptotic factors COX-2 and ACSL4 was upregulated, while the expression of TFRC, FIH1, SLC7A11, and GPX4 was downregulated. The NF-κB pathway (p-p65, IκBα), inflammatory cytokines (TNF-α, IL-8, IL-6) and apoptosis genes (Bax, Caspase3) were upregulated. Semi-quantitative detection of related proteins by Western blotting was consistent with the gene expression results. In addition, the ELISA assay showed that lipid peroxidation and inflammatory cytokines (TNF-α, IL-1ß, IL-6) were increased in the microplastic exposed group. To conclude, lipid peroxidation induced by microplastics activates the NF-κB pathway and causes ferroptosis, ultimately resulting in intestinal damage and cellular apoptosis.


Asunto(s)
Carpas , Ferroptosis , Contaminantes Químicos del Agua , Animales , FN-kappa B/metabolismo , Microplásticos/toxicidad , Plásticos/toxicidad , Transducción de Señal , Factor de Necrosis Tumoral alfa , Interleucina-6/toxicidad , Interleucina-6/uso terapéutico , Carpas/metabolismo , Contaminantes Químicos del Agua/toxicidad , Inflamación/inducido químicamente , Inflamación/metabolismo , Citocinas/genética , Apoptosis
7.
Langmuir ; 39(25): 8737-8748, 2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37294901

RESUMEN

The introduction of the concept of surface properties can help us to better analyze the basic physicochemical property changes of metal-organic framework (MOF) materials before and after fluorine functional group treatment. In this study, several polar and nonpolar probes were selected to determine the surface properties, including surface-dispersive free energy, Lewis acid-base constants of Ni-MOF-74, and perfluoro carboxylic acid-modified Ni-MOF-74-Fn (n = 3, 5, and 7) in the range of 343.15-383.15 K by inverse gas chromatography (IGC). It was observed that the surface energy of the treated Ni-MOF-74-Fn showed a substantial decrease with the growth of the perfluorocarbon alkyl chains and the increase in surface roughness. In addition, Lewis acidic sites exposed by the Ni-MOF-74 material after adopting modification with fluorine functional groups increased with the increase of perfluorinated carboxylic acid chains, and their surface properties changed from amphiphilic acidic to strongly acidic. These results not only enrich the basic physical property data of Ni-MOF-74 but also provide more theoretical basis for the fluorinated functionalized custom-designed MOFs and enrich their applications in the fields of multiphase catalysis, gas adsorption, and chromatographic separation.

8.
Fish Shellfish Immunol ; 138: 108847, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37230306

RESUMEN

Selenium (Se), one of the essential trace elements of fish, regulates immune system function and maintains immune homeostasis. Muscle is the important tissue that generate movement and maintain posture. At present, there are few studies on the effects of Se deficiency on carp muscle. In this experiment, carps were fed with dietary with different Se content to successfully establish a Se deficiency model. Low-Se dietary led to the decrease of Se content in muscle. Histological analysis showed that Se deficiency resulted in muscle fiber fragmentation, dissolution, disarrangement and increased myocyte apoptosis. Transcriptome revealed a total of 367 differentially expressed genes (DEGs) were screened, including 213 up-regulated DEGs and 154 down-regulated DEGs. Bioinformatics analysis showed that DEGs were concentrated in oxidation-reduction process, inflammation and apoptosis, and were related to NF-κB and MAPKs pathways. Further exploration of the mechanism showed that Se deficiency led to excessive accumulation of ROS, decreased the activity of antioxidant enzymes, and also resulted in increased expression of the NF-κB and MAPKs pathways. In addition, Se deficiency significantly increased the expressions of TNF-α, IL-1ß and IL-6, and the pro-apoptotic factors BAX, p53, caspase-7 and caspase-3, while decreased the expressions of anti-apoptotic factors Bcl-2 and Bcl-xl. In conclusion, Se deficiency reduced the activities of antioxidant enzymes and led to excessive accumulation of ROS, which caused oxidative stress and affected the immune function of carp, leading to muscle inflammation and apoptosis.


Asunto(s)
Carpas , Desnutrición , Selenio , Animales , Antioxidantes/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Suplementos Dietéticos , Selenio/metabolismo , Carpas/genética , Carpas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Inmunidad Innata , Transducción de Señal , Inflamación/veterinaria , Apoptosis , Músculos/metabolismo
9.
RSC Adv ; 13(20): 13365-13373, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37143919

RESUMEN

Silicon-based anode materials have been applied in lithium-ion batteries with high energy density. However, developing electrolytes that can meet the specific requirements of these batteries at low temperatures still remains a challenge. Herein, we report the effect of linear carboxylic ester ethyl propionate (EP), as the co-solvent in a carbonate-based electrolyte, on SiO x /graphite (SiOC) composite anodes. Using electrolytes with EP, the anode provides better electrochemical performance at both low temperatures and ambient temperature, showing a capacity of 680.31 mA h g-1 at -50 °C and 0.1C (63.66% retention relative to that at 25 °C), and a capacity retention of 97.02% after 100 cycles at 25 °C and 0.5C. Within the EP-containing electrolyte, SiOC‖LiCoO2 full cells also exhibit superior cycling stability at -20 °C for 200 cycles. These substantial improvements of the EP co-solvent at low temperatures are probably due to its involvement to form a solid electrolyte interphase with high integrity and facile transport kinetics in electrochemical processes.

10.
Artículo en Inglés | MEDLINE | ID: mdl-36833627

RESUMEN

The definition of 'soundscape' emphasises the perceptual construct of sounds; thus, the mechanism of sound perceptions becomes vital for soundscape evaluations. Using a qualitative approach, this study explored the aspects and processes of sound perceptions and built a perceptual soundscape structure from the insight of sociology. The interview was conducted between January and March 2018, in four urban public spaces. Data reached saturation after 23 participants were interviewed based on the grounded theory approach. Four perceptual aspects of sounds were identified from the semantic coding analysis: sound classification, sound features, psychological reactions, and soundscape preferences. These aspects form a three-level process of perceiving soundscapes: sound classifications, sound appraisals (including sound features and psychological reactions), and finally, judgment (soundscape preferences). Overall, four aspects categorised into three levels of perception make up the soundscape structure. Soundscape preferences are at the most profound level of perception and are informed by the previous three aspects. Soundscape preferences are expressed through descriptive words and narrative 'image'. The 'image' reflects people participating in different activities according to their social background. Social relationships influence soundscape preferences through people's sound requirements for various activities. The perceptual structure of soundscapes may provide guidance for future soundscape research and soundscape questionnaire design.


Asunto(s)
Semántica , Sonido , Humanos , Teoría Fundamentada , Ambiente , Audición , Acústica
11.
Environ Pollut ; 320: 121068, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36641069

RESUMEN

Microplastics are ubiquitous pollutants with a wide range of plastic applications. More recently, microplastics are in the air and can be inhaled into the lungs, causing respiratory diseases. Knowledge of the underlying mechanisms by which microplastics may induce respiratory disease is still limited. This study used intranasal instillation to develop a model of lung injury. The histopathology result showed that the mouse lung had severe inflammatory responses, apoptosis and collagen deposition with chronic exposure to different sizes (Small: 1-5 µm and Large: 10-20 µm) of polystyrene microplastics (PS-MPS), and the damage of smaller sizes was obvious. The expression levels of the Toll-like receptors (TLRs) family, evolutionarily conserved pattern recognition receptors, were detected, and the levels of TLR2 mRNA was significantly increased. In transfection experiments, PS-MPS increased the inflammatory response in HEK293 cells with TLR2 expression. Furthermore, exposure to small polystyrene microplastics promoted oxidative stress and apoptosis, and accelerated the process of fibrosis. Interestingly, inhibition of the NF-κB signal relieves inflammation and oxidative stress, reduces apoptosis, and thus controls the fibrosis process. These results suggested that PS-MPS targeted binding to TLR2 and further exacerbated fibrosis by facilitating inflammation, oxidative stress, and apoptosis with the activation of NF-κB signal.


Asunto(s)
Lesión Pulmonar , Microplásticos , Ratones , Humanos , Animales , Microplásticos/toxicidad , Poliestirenos/toxicidad , FN-kappa B/metabolismo , Plásticos , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Lesión Pulmonar/inducido químicamente , Células HEK293 , Inflamación/metabolismo , Fibrosis
12.
Fish Shellfish Immunol ; 132: 108470, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36470402

RESUMEN

Microplastics cause varying degrees of damage to aquatic organisms. Exposure to microplastics contaminated water, the gills are among the first tissues, after the skin, to be affected by microplastics. As an essential immune organ, prolonged stimulation by microplastics disrupts immune function not only in the gills but throughout the body, yet the underlying mechanisms remain elusive. A model of gill injury from exposure to polyethylene (PE) microplastics was developed in this study. H&E staining revealed that polyethylene microplastics caused gill inflammation, vascular remodeling, and mucous cell proliferation. An increase in collagen indicates severe tissue damage. Additional analysis showed that polyethylene microplastics profoundly exacerbated oxidative stress in the gills. TUNEL assay demonstrated cell apoptosis induced by polyethylene microplastic. The mRNA levels were subsequently quantified using RT-PCR. The results showed that polyethylene microplastics increased the expression of the nuclear factor-κB (NF-κB) pathway (NF-κB p65, IKKα, IKKß) and apoptosis biomarkers (p53, caspase-3, caspase-9, and Bax). Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasomes, which is an influential component of innate immunity, were overactive. What's more, the pro-inflammatory factors (TNF-α, IFN-γ, IL-2, IL-6, IL-8, IL-1ß) that induce immune disorder also increased significantly, while the anti-inflammatory factors (IL-4, IL-10) decreased significantly. These results suggested that oxidative stress acted as an activation signal of apoptosis triggered by the NF-κB pathway and activating the NLRP3 inflammasome to promote inflammatory immune responses. The present study provided a different target for the prevention of toxin-induced gill injury under polyethylene microplastics.


Asunto(s)
Carpas , Inflamasomas , Animales , FN-kappa B/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Microplásticos/toxicidad , Plásticos , Branquias/metabolismo , Polietileno , Transducción de Señal , Carpas/metabolismo , Inflamación/inducido químicamente , Inflamación/veterinaria , Inflamación/metabolismo , Apoptosis , Estrés Oxidativo
13.
Metabolites ; 12(11)2022 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-36355092

RESUMEN

Tea polyphenols (TPs) are the main active substances in tea and they have many beneficial effects, such as anti-inflammation, antioxidant, anti-cancer and metabolic regulation effects. The quality of milk is affected by mammary gland diseases and there are substantial economic losses resulting from reduced milk production as a consequence of inflammatory injury of the mammary gland. In this study, transcriptome analysis and molecular biology techniques were used to study the effects of TPs on inflammatory injury of the mammary gland. After intervention with TPs, a total of 2085 differentially expressed genes were identified, including 1189 up-regulated genes and 896 down-regulated genes. GO analysis showed that differentially expressed genes played an important role in proton transmembrane transport, oxidation-reduction reactions and inflammatory response. KEGG enrichment suggested that differential genes were concentrated in the TGF-ß pathway and active oxygen metabolism process. Experiments were performed to confirm that TPs increased SOD, CAT, T-AOC and GSH-Px content along with a reduction in MDA. Meanwhile, TPs inhibited the expression of TGF-ß1 and reduced the phosphorylation of p38 and JNK. The expression of inflammatory cytokines IL-1ß, IL-6 and TNF-α were significantly decreased after intervention with TPs. In summary, all the data indicated that TPs protected the mammary gland by enhancing the antioxidant capacity and down-regulating the TGF-ß1/p38/JNK pathway.

14.
Front Microbiol ; 13: 961885, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35935245

RESUMEN

Background: Inflammatory bowel disease (IBD), a disease that seriously harms human and animal health, has attracted many researchers' attention because of its complexity and difficulty in treatment. Most research has involved rats and dogs, and very little was cats. We should know that gut microbiota varies significantly from animal to animal. Traditional Chinese Medicine and its monomer component have many advantages compared with antibiotics used in pet clinics. Numerous studies have shown berberine (berberine hydrochloride) therapeutic value for IBD. However, the specific mechanism remains to consider. Results: We assessed gut pathology and analyzed fecal bacterial composition using Histological staining and 16S rRNA sequence. Dioctyl sodium sulfosuccinate (DSS) administration destroyed intestinal mucosal structure and changed the diversity of intestinal flora relative to control. RT-PCR and western blot confirmed specific molecular mechanisms that trigger acute inflammation and intestinal mucosal barrier function disruption after DSS treatment. And autophagy inhibition is typical pathogenesis of IBD. Interestingly, berberine ameliorates inflammation during the development of the intestinal by modulating the toll-like receptors 4 (TLR4)/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway and activating autophagy. Berberine significantly reduces tumor necrosis factor α (TNF-α), interleukin (IL)-6, and IL-1ß expression in cats' serum. Enhancing the antioxidant effect of IBD cats is one of the protective mechanisms of berberine. We demonstrated that berberine repairs intestinal barrier function by activating the mammalian target of rapamycin (mTOR) complex (MTORC), which inhibits autophagy. Conclusion: Berberine can restore intestinal microbiota homeostasis and regulate the TLR4/NF-κB pathway, thereby controlling inflammatory responses. We propose a novel mechanism of berberine therapy for IBD, namely, berberine therapy can simultaneously activate MTORC and autophagy to restore intestinal mucosal barrier function in cats, which should be further studied to shed light on berberine to IBD.

15.
Phys Chem Chem Phys ; 24(18): 11023-11029, 2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35470357

RESUMEN

A new ice phase, ice XIX, was discovered in 2018, and is the second hydrogen-ordered polymorph of hydrogen-disordered ice VI. The first hydrogen-ordered polymorph of ice VI is ice XV, and ices XIX, VI, and XV comprise a unique triplet group in the ice family. However, the exact crystal structure of ice XIX has not been confirmed. We constructed four possible conformations of ice XIX using neutron diffraction data obtained by Gasser et al. We then optimized these structures and simulated their Raman scattering spectra using first-principles density functional theory. By comparing these simulated spectra with the experimental Raman scattering spectra, we were able to exclude the existence of a ferroelectric structure with the space group Cc. The other three candidate structures are in good agreement with the experimental Raman scattering data; two of them are ferroelectric structures with the space group P21; and the last one is a weak ferroelectric structure with the space group Cc. We proposed that the partially hydrogen-ordered structure of ice XIX maybe a mixing of several hydrogen-ordered structures.

16.
ACS Omega ; 7(6): 5437-5441, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35187359

RESUMEN

Rhenium (Re) is an extremely rare and precious element that is mainly used in the construction of aerospace components and satellite stations. However, an efficient and simple method for preparing Re has yet to be devised. To this end, we investigated the vibrational spectrum of ammonium perrhenate (NH4ReO4) using the CASTEP code based on first-principles density functional theory. We assigned the infrared (IR) absorption and Raman scattering spectra for NH4ReO4 using a dynamic process analysis of optical branch normal modes. We examined the IR-active peaks of Re-related vibrational modes in detail and found that the typical IR peak at approximately 914 cm-1 is due to the Re-O bond stretching. Thus, we posit that strong terahertz laser irradiation of NH4ReO4 at 914 cm-1 will lead to sufficient resonance absorption to cleave its Re-O bonds. This method could potentially be used to efficiently separate Re from its oxides.

17.
ACS Omega ; 7(3): 2970-2974, 2022 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-35097289

RESUMEN

It is difficult to theoretically study the vibrational spectrum of hydrogen-disordered ice XII compared with its hydrogen-ordered counterpart, ice XIV. We constructed a 24-molecule supercell of ice XII to mimic its real structure. We focused on hydrogen bond (HB) vibrational modes in the translation band using first-principles density functional theory (DFT). Our simulated results were in good agreement with inelastic neutron scattering experiments. We found that the optical vibrational modes of HBs are composed of three main components. These are cluster vibrations in the lowest-frequency region, four-bond HB vibrations in the highest-frequency region, and two-bond modes in between. Although the experimentally recorded curve of ice XII is smooth in the translation region, our results support the proposal that two types of intrinsic HB vibrational modes are common in the ice family.

18.
ACS Omega ; 6(22): 14442-14446, 2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-34124466

RESUMEN

It is difficult to investigate the hydrogen-bonding dynamics of hydrogen-disordered ice VI. Here, we present a comparative method based on our previous study of its counterpart hydrogen-ordered phase, ice XV. The primitive cell of ice XV is a 10 molecule unit, and the vibrational normal modes were analyzed individually. We constructed an 80 molecule supercell of ice VI to mimic the periodic unit and performed first-principles density functional theory calculations. As the two vibrational spectra show almost identical features, we compared the molecular translation vibrations. Inspired by the phonon analysis of ice XV, we found that the vibrational modes in the translation band of ice VI are classifiable into three groups. The lowest-strength vibration modes represent vibrations between two sublattices that lack hydrogen bonding. The highest-strength vibration modes represent the vibration of four hydrogen bonds of one molecule. The middle-strength vibration modes mainly represent the molecular vibrations of only two hydrogen bonds. Although there are many overlapping stronger and middle modes, there are only two main peaks in the inelastic neutron scattering (INS) spectra. This work explains the origin of the two main peaks in the far-infrared region of ice VI and illustrates how to analyze a hydrogen-disordered ice structure.

19.
Sci Bull (Beijing) ; 65(10): 812-819, 2020 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-36659199

RESUMEN

Fiber-shaped energy storage devices areindispensableparts of wearable and portable electronics. Aqueous rechargeable Ni/Fe battery is a very appropriate energy storage device due to their good safety without organic electrolytes, high ionic conductivity, and low cost. Unfortunately, the low energy density, poor power density and cycling performance hinder its further practical applications. In this study, in order to obtain high performance negative iron-based material, we first synthesized α-iron oxide (α-Fe2O3) nanorods (NRs) with superstructures on the surface of highly conductive carbon nanotube fibers (CNTFs), then electrically conductive polypyrrole (PPy) was coated to enhance the electron, ion diffusion and cycle stability. Theas-prepared α-Fe2O3@PPy NRs/CNTF electrode shows a high specific capacity of 0.62 Ah cm-3 at the current density of 1 A cm-3. Furthermore, the Ni/Fe battery that was assembled by the above negative electrode shows a maximum volumetric energy density of 15.47 mWh cm-3 with 228.2 mW cm-3 at a current density of 1 A cm-3. The cycling durability and mechanical flexibility of the Ni/Fe battery were tested, which show good prospect for practical application. In summary, these merits make it possible for our Ni/Fe battery to have practical applications in next generation flexible energy storage devices.

20.
Biol Trace Elem Res ; 196(1): 145-152, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31625053

RESUMEN

Zinc (Zn) is an important trace element in the body that has antioxidant effects. It has been proven that Zn deficiency can cause oxidative stress. The purpose of the present study was to clarify the effect and mechanism of Zn deficiency on myocardial fibrosis. Mice were fed with different Zn levels dietary for 9 weeks: Zn-normal group (ZnN, 34 mg Zn/kg), Zn-deficient group (ZnD, 2 mg Zn/kg), and Zn-adequate group (ZnA, 100 mg Zn/kg). We found that the Zn-deficient diet reduced the Zn concentration in myocardial tissue. Moreover, the TUNEL results demonstrated that cardiomyocytes in the ZnD group died in large numbers. Furthermore, ROS levels were significantly increased, and metallothionein (MT) expression levels decreased in the ZnD group. The results of Sirius Red staining indicated an increase in collagen in the ZnD group. Moreover, the ELISA results showed that collagen I, III, and IV and fibronectin (FN) were increased. In addition, the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) was detected by RT-qPCR. The results showed that the expression of TIMP-1 in the ZnD group was increased, while MMPs were decreased. Immunohistochemical results showed an increase in the content of α-smooth muscle actin (α-SMA), while H&E staining showed an increase in interstitial width and a decrease in the number of cardiac cells. All data suggest that Zn deficiency enhances the oxidative stress response of myocardial tissue and eventually triggers myocardial fibrosis.


Asunto(s)
Fibrosis/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Metaloproteasas/metabolismo , Miocardio/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Zinc/metabolismo , Animales , Dieta , Masculino , Ratones , Ratones Endogámicos BALB C , Especies Reactivas de Oxígeno/análisis , Zinc/administración & dosificación , Zinc/deficiencia
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