Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 150
Filtrar
1.
J Phys Chem Lett ; : 9575-9584, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269336

RESUMEN

Ligand engineering of aromatic heterocyclic cations in two-dimensional (2D) Dion-Jacobson (DJ) perovskites has been widely explored in recent years. In this study, how the positional isomers of aromatic heterocyclic cations tune the lattice of 2D perovskites, thereby influencing the transport and recombination dynamics of charge carriers, has been investigated through nonadiabatic molecular dynamics simulations. We demonstrate that the meta-substituted 3-(aminomethyl)pyridinium (3AMPY) cations greatly reduce the strength of electron-vibration coupling since the strong hydrogen-bonding network introduced by the changes in the arrangement of spacer cations significantly suppresses the structural thermal fluctuations. Compared to the para-substituted 4-(aminomethyl)pyridinium (4AMPY) cation, using the asymmetric 3AMPY as a spacer cation can achieve improved in-plane transport performance, enhanced thermal stability, and suppressed charge carrier recombination through weakening electron-vibration interactions. Our results explain the observed lifetime difference between the two types of DJ-phase perovskites in experiments and provide new guidance for optimizing the performance of perovskite devices.

2.
Chem Sci ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39139736

RESUMEN

There exists an interplay between borane and a Lewis base in their adducts. However, studies on these adducts so far have mainly focused on the different reactions of B-H bonds with limited attention given to the influence of borane on the chemistry of the Lewis base, except for BF3 and BAr3. Herein, we have synthesized novel borane adducts with pyridine derivatives, Py·B3H7, in which the coordination of B3H7 efficiently achieved the intra-molecular charge transfer. The strong B-N bond in these adducts resulted in the formation of stable dearomatic intermediates of pyridine derivatives, confirmed by 1H and 11B NMR spectroscopy, from which different reactions have transpired to realize C(sp3)-H and C(sp2)-H functionalization under mild conditions. The B3H7 pyridine derivatives are stable and do not dissociate or decompose during the reaction process. The high stability of the B-N bond makes this method a good option for boron-containing drugs with potential for use in boron neutron capture therapy (BNCT).

3.
Plants (Basel) ; 13(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39124249

RESUMEN

Chimonanthus praecox, a member of the Calycanthaceae family, is a unique, traditional, and famous flowering economic tree species in China. Despite the existence of several varieties, only a few cultivars have been formally named. Currently, expression sequence tag-simple sequence repeat (EST-SSR) markers are extensively used to identify different species and varieties; a large number of microsatellites can be identified from transcriptome databases. A total of 162,638 unigenes were assembled using RNA-seq; 82,778 unigenes were annotated using the Nr, Nt, Swiss-Prot, Pfam, GO, KOG, and KEGG databases. In total, 13,556 SSR loci were detected from 11,691 unigenes, with trinucleotide repeat motifs being the most abundant among the six repeat motifs. To develop the markers, 64,440 pairs of SSR primers with polymorphism potential were designed, and 75 pairs of primers were randomly selected for amplification. Among these markers, seven pairs produced amplified fragments of the expected size with high polymorphism. Using these markers, 12 C. praecox varieties were clustered into two monophyletic clades. Microsatellites in the transcriptome of C. praecox exhibit rich types, strong specificity, and great polymorphism potential. These EST-SSR markers serve as molecular technical methods for identifying different varieties of C. praecox and facilitate the exploration of a large number of candidate genes associated with important traits.

4.
J Colloid Interface Sci ; 674: 884-893, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38955019

RESUMEN

Silver (Ag) recovery is essential for ecological protection, human health and economic benefits. Effective capture of Ag(I) from wastewater is still challenging due to insufficient accessible sites of adsorbents. Herein, an acyl chloride-mediated strategy is developed to synthesize rhodanine (Rd) modified UiO-66 derivatives for Ag(I) adsorption. Benefitting from the high grafting density of Rd, the optimal Rd-modified UiO-66-NH2 (UiO-66-NH2@20Rd) features an ultra-high uptake capacity (maximum capacity of 923.9 mg·g-1) and selectivity (maximum selectivity coefficient of 1665.52) for Ag(I). Almost 90 % of Ag(I) could be captured in one minute over UiO-66-NH2@20Rd and maintained a removal rate of 98.9 % even after six cycles. Moreover, a fixed-bed column test demonstrates that approximately 21,780 bed volumes of Ag(I) simulated wastewater can be effectively treated, indicating great promise for practical application. Mechanism investigation illustrates that outstanding performance can be attributed to the synergistic effect of Ag(I) adsorption and reduction on dense rhodanine sites. This study highlights that such a general strategy can provide a valuable avenue toward various functional adsorption materials.

5.
Heliyon ; 10(11): e32027, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38868037

RESUMEN

Objective: Understanding the characteristics of alveolar bone resorption in an East Asian population after maxillary incisor extraction and providing a reference for implant treatment plans. Study design: Cone-beam computerized tomography (CBCT) data of 125 East Asian patients with unilateral extraction of maxillary incisors for 3 months were collected. The alveolar bone width and height in the extraction sites were measured and compared with the corresponding contralateral sites. Results: The differences in alveolar bone width between the extraction site and contralateral site were as follows: 4.11 mm, 2.68 mm, and 2.09 mm (3 mm, 5 mm, 7 mm apical from CEJ of the contralateral tooth). Data are expressed as the median. The horizontal resorption ratio of alveolar bone was 49.94 %, 31.5 %, and 24.46 %. The difference in alveolar bone height was 0.78 mm. The vertical resorption ratio was 7.78 %. The resorption did not differ significantly between sexes and was not significantly affected by tooth positions. Conclusions: In the studied East Asian population, significant horizontal and vertical alveolar bone resorption occurs after natural healing of maxillary incisor extraction for 3 months. The closer to the alveolar ridge crest, the more significant the horizontal resorption, resulting in an "inverted triangle" shape residual alveolar bone.

6.
Toxics ; 12(5)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38787130

RESUMEN

Untreated or inadequately treated silver-containing wastewater may pose adverse effects on hu-man health and the ecological environment. Currently, significant progress has been made in the treatment of Ag(I) in wastewater using adsorption methods, with adsorbents playing a pivotal role in this process. This paper provides a systematic review of various adsorbents for the recovery and treatment of Ag(I) in wastewater, including MOFs, COFs, transition metal sulfides, metal oxides, biomass materials, and other polymeric materials. The adsorption mechanisms of these materials for Ag(I) are elaborated upon, along with the challenges currently faced. Furthermore, insights into optimizing adsorbents and developing novel adsorbents are proposed in this study.

7.
Arch Virol ; 169(5): 115, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709425

RESUMEN

Porcine circoviruses (PCVs) are a significant cause of concern for swine health, with four genotypes currently recognized. Two of these, PCV3 and PCV4, have been detected in pigs across all age groups, in both healthy and diseased animals. These viruses have been associated with various clinical manifestations, including porcine dermatitis and nephropathy syndrome (PDNS) and respiratory and enteric signs. In this study, we detected PCV3 and PCV4 in central China between January 2022 and February 2023. We tested fecal swabs and tissue samples from growing-finishing and suckling pigs with or without respiratory and systemic manifestations and found the prevalence of PCV3 to be 15.15% (15/99) and that of PCV3/PCV4 coinfection to be 4.04% (4/99). This relatively low prevalence might be attributed to the fact that most of the clinical samples were collected from pigs exhibiting respiratory signs, with only a few samples having been obtained from pigs with diarrhea. In some cases, PCV2 was also detected, and the coinfection rates of PCV2/3, PCV2/4, and PCV2/3/4 were 6.06% (6/99), 5.05% (5/99), and 3.03% (3/99), respectively. The complete genomic sequences of four PCV3 and two PCV4 isolates were determined. All four of the PCV3 isolates were of subtype PCV3b, and the two PCV4 isolates were of subtype PCV4b. Two mutations (A24V and R27K) were found in antibody recognition domains of PCV3, suggesting that they might be associated with immune escape. This study provides valuable insights into the molecular epidemiology and evolution of PCV3 and PCV4 that will be useful in future investigations of genotyping, immunogenicity, and immune evasion strategies.


Asunto(s)
Infecciones por Circoviridae , Circovirus , Genotipo , Filogenia , Enfermedades de los Porcinos , Circovirus/genética , Circovirus/aislamiento & purificación , Circovirus/clasificación , Animales , Porcinos , China/epidemiología , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/epidemiología , Infecciones por Circoviridae/veterinaria , Infecciones por Circoviridae/virología , Infecciones por Circoviridae/epidemiología , Coinfección/virología , Coinfección/veterinaria , Coinfección/epidemiología , Genoma Viral/genética , Heces/virología
8.
Inorg Chem ; 63(23): 10519-10526, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38804144

RESUMEN

The BCN-heterocyclic B-N chain compounds, the sodium and potassium salts of 3 and 4 anions (Na3, Na4, and K4), were synthesized by reactions of ethane 1,2-diamineborane (BH3NH2CH2CH2NH2BH3, 1) and propane 1,2-diamineborane (BH3NH2CH2CH2CH2NH2BH3, 2) with MH (M = Na and K). Then, the neutral B-N chain compounds 5 and 6 were prepared with dehydrogenation of [NH4]3 and [NH4]4, formed by metathesis reactions of Na3 and Na4 with NH4Cl or NH4SCN, respectively. Compounds 7 and 8, analog 5, were also prepared using pyridine and 4-methoxypyridine instead of NH3 in 5. These synthesized compounds were characterized spectroscopically, and the singe-crystal structures of the Na3·18-crown-6 and K4·18-crown-6 adducts were determined. Furthermore, the reactions of Na3 and Na4 with cationic B-N chain compounds, [NH3BH2NH3]Cl and [NH3BH2NH2BH2NH3]Cl, could not form longer BCN-heterocyclic B-N chain. The solubility of metal hydrides, the ability for proton abstracting, the basicity of Lewis bases, and the chelate effect may influence these reactions even though the reaction mechanism is not fully understood.

9.
Ther Clin Risk Manag ; 20: 161-168, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476881

RESUMEN

Background: Studies of chylothorax after congenital heart disease in infants are rare. Chylothorax has a higher incidence in infancy, but its risk factors are not well understood. Objective: The purpose of this study is to investigate the risk factors of chylothorax after congenital heart surgery in infants. Methods: This retrospective study included 176 infants who underwent congenital heart disease surgery at the Guangdong Cardiovascular Institute, China, between 2016 and 2020. According to the occurrence of chylothorax, the patients were divided into a control group (n = 88) and a case group (n = 88). Univariate and multivariate logistic regression were performed to analyse the incidence and influencing factors of chylothorax after congenital heart surgery in infants. Results: Between 2016 and 2020, the annual incidence rate fluctuated between 1.55% and 3.17%, and the total incidence of chylothorax was 2.02%. Multivariate logistic regression analysis showed that postoperative albumin (p = 0.041; odds ratio [OR] = 0.095), preoperative mechanical ventilation (p = 0.001; OR = 1.053) and preterm birth (p = 0.002; OR = 5.783) were risk factors for postoperative chylothorax in infants with congenital heart disease. Conclusion: The total incidence of chylothorax was 2.02% and the annual incidence rate fluctuated between 1.55% and 3.17% between 2016 and 2020. Premature infants, longer preoperative mechanical ventilation and lower albumin after congenital heart surgery may be risk factors for chylothorax. In addition, infants with chylothorax are inclined to be infected, need more respiratory support, use a chest drainage tube for longer and remain longer in hospital.

10.
Chin J Dent Res ; 27(1): 47-52, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38546519

RESUMEN

MN1 C-terminal truncation (MCTT) syndrome was first reported in 2020 and only 28 patients have been recorded to date. Since MCTT syndrome is a newly defined and rare syndrome with many clinical features, the present study reviewed the manifestations and management of oral and dental anomalies. Gene variants of MCTT syndrome and their positive phenotypes were summarised. The phenotypes of variants in two exons differed from each other mainly in the craniomaxillofacial region, including brain MRI abnormalities and palatal morphology. Pathogenic mechanisms, especially in craniofacial and oral anomalies, were discussed. Appropriate treatments in the stomatology and respiratory departments could improve the symptoms of MCTT syndrome. The different sites of MN1 gene variants may influence the clinical symptoms and there may be racial differences in MCTT syndrome. We recommend oral and pulmonary evaluations for the multidisciplinary treatment of MCTT syndrome.


Asunto(s)
Encefalopatías , Medicina Oral , Humanos , Exones , Estudios Interdisciplinarios , Neuroimagen , Transactivadores , Proteínas Supresoras de Tumor
11.
PLoS Pathog ; 20(1): e1011893, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38166140

RESUMEN

The hygiene hypothesis proposes that decreased exposure to infectious agents in developed countries may contribute to the development of allergic and autoimmune diseases. Trichinella spiralis, a parasitic roundworm, causes trichinellosis, also known as trichinosis, in humans. T. spiralis had many hosts, and almost any mammal could become infected. Adult worms lived in the small intestine, while the larvae lived in muscle cells of the same mammal. T. spiralis was a significant public health threat because it could cause severe illness and even death in humans who eat undercooked or raw meat containing the parasite. The complex interactions between gastrointestinal helminths, gut microbiota, and the host immune system present a challenge for researchers. Two groups of mice were infected with T. spiralis vs uninfected control, and the experiment was conducted over 60 days. The 16S rRNA gene sequences and untargeted LC/MS-based metabolomics of fecal and serum samples, respectively, from different stages of development of the Trichinella spiralis-mouse model, were examined in this study. Gut microbiota alterations and metabolic activity accompanied by parasite-induced immunomodulation were detected. The inflammation parameters of the duodenum (villus/crypt ratio, goblet cell number and size, and histological score) were involved in active inflammation and oxidative metabolite profiles. These profiles included increased biosynthesis of phenylalanine, tyrosine, and tryptophan while decreasing cholesterol metabolism and primary and secondary bile acid biosynthesis. These disrupted metabolisms adapted to infection stress during the enteral and parenteral phases and then return to homeostasis during the encapsulated phase. There was a shift from an abundance of Bacteroides in the parenteral phase to an abundance of probiotic Lactobacillus and Treg-associated-Clostridia in the encapsulated phase. Th2 immune response (IL-4/IL-5/IL-13), lamina propria Treg, and immune hyporesponsiveness metabolic pathways (decreased tropane, piperidine and pyridine alkaloid biosynthesis and biosynthesis of alkaloids derived from ornithine, lysine, and nicotinic acid) were all altered. These findings enhanced our understanding of gut microbiota and metabolic profiles of Trichinella -infected mice, which could be a driving force in parasite-shaping immune system maintenance.


Asunto(s)
Microbioma Gastrointestinal , Trichinella spiralis , Triquinelosis , Ratones , Humanos , Animales , ARN Ribosómico 16S , Inflamación , Inmunidad , Redes y Vías Metabólicas , Inmunomodulación , Mamíferos
13.
Chinese Pharmacological Bulletin ; (12): 234-242, 2024.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1013621

RESUMEN

Aim To investigate the regulatory effect of Cortaetin on pathological myocardial hypertrophy induced by isoprenaline (ISO) and the underlying mechanism. Methods ISO was used to stimulate neonatal rat cardiomyocytes for 24 h, and myocardial hypertrophy model was established at the cellular level. C57BL/6 mice were injected subcutaneously with ISO for one week to establish myocardial hypertrophy model at animal level. RT-qPCR was used to detect the changes of mRNA and Western blot was used to detect the changes of relative protein content. Immunofluorescence was used to measure the subcellular location of Cortaetin and the change of its expression. The overex-pression of Cortaetin by adenovirus infection and the knockdown of Cortaetin by transfection of small interfering RNA were studied. Results On the cellular and animal levels, ISO-induced myocardial hypertrophy models were successfully established, and it was observed that ISO caused the decrease of Cortaetin and N-cadherin protein levels. Overexpression of Cortaetin could reverse the decrease of N-cadherin protein level and myocardial hypertrophy caused by ISO. Knockdown of Cortaetin showed the opposite effect. Conclusion Cortaetin, in combination with N-cadherin, may play a role in combating myocardial hypertrophy by enhancing the connections between cardiomyocytes.

14.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1027405

RESUMEN

Immunotherapy has entered the clinical treatment for various tumors, among which the blockade therapy of PD-1/PD-L1 immune checkpoint is currently the most important tumor immunotherapy method. At present, immunohistochemical method are used in clinical practice to detect PD-L1 expression in tumor patients and screen for indications. However, this method is constrained by factors such as heterogeneity, dynamic changes in PD-L1 expression, and limited sample collection. PD-(L)1 PET imaging utilizes radiolabeled molecules to non-invasively assess PD-(L)1 expression in space and time, and complementary use with IHC has theoretically incomparable advantages. This article reviews the latest progress in the PD-(L)1 probe molecular imaging principles, clinical research and existing problems.

15.
Medicine (Baltimore) ; 102(48): e36297, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38050208

RESUMEN

BACKGROUND: Breast cancer is one of the most common type of cancers worldwide and remains a critical health issue. Although there are numerous treatment options for advanced metastatic breast cancer, the results are not satisfactory, particularly for triple-negative breast cancer. New treatment modalities need to be explored. CASE PRESENTATION: We present the case of a breast cancer patient with multiple metastases who achieved a good response and tolerance to the combination treatment of utidelone plus capecitabine. After being treated with 10 cycles of combined treatment, the patient is now in a good general condition with a progression-free survival time of 10 months. CONCLUSION: To our knowledge, this is the first report of utidelone plus capecitabine successfully treating a patient with heavily pretreated metastatic breast cancer. This combined treatment offers a new option for patients with multi-drug resistant breast cancer.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Capecitabina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Terapia Combinada , Supervivencia sin Progresión , Fluorouracilo/uso terapéutico
16.
Dalton Trans ; 52(47): 17684-17688, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37999641

RESUMEN

An efficient method for the synthesis of M2B10H14 (M = Na and K) has been developed. The two possible formation mechanisms of the B10H142- anion are proposed, in which the NH2BH3- anion acts as a proton abstractor and a hydride donor. Furthermore, the B10H13- and B10H15- intermediates were detected.

17.
Zhongguo Zhen Jiu ; 43(11): 1279-1286, 2023 Oct 10.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-37984922

RESUMEN

OBJECTIVES: To explore the effect mechanism of electroacupuncture (EA) on functional constipation (FC) at the combined lower he-sea and front-mu points of large intestine based on enteric neuronal autophagy. METHODS: A total of 40 SPF Kunming mice were randomly divided into 5 groups (n = 8), i.e. a control group, a model group, an acupuncture group, a 3-methyl adenine (3-MA) group, and a 3-MA + acupuncture group. Except the control group, the FC model was established by gavage with compound diphenoxylate suspension for 14 days in the other 4 groups. After successful modeling, the mice of the acupuncture group and the 3-MA + acupuncture group received EA at bilateral "Tianshu" (ST 25) and "Shangjuxu" (ST 37), stimulated for 30 min with disperse-dense wave, 2 Hz/15 Hz of frequency, 1 mA of intensity. EA was delivered once daily. One course of treatment was composed of 5 days and 2 courses were needed, with an interval of 2 days. An intraperitoneal injection of 3-MA (15 mg/kg) was administered 30 min before EA in the mice of the 3-MA group and the 3-MA + acupuncture group, once daily. Before and after intervention, the time of the first black stool defecation and defecation behaviors in 6 h were observed in each group. After intervention, in every group, the small intestine propulsion rate was calculated, the colon tissue morphology was observed using HE staining, the ultrastructure of enteric neuronal autophagy was observed under transmission electron microscope, and the expressions of microtubule-associated protein 1 light chain 3 (LC3), Beclin-1 and neuronal nuclear antigen protein (NeuN) in neurons of colonic muscularis were determined by immunohistochemistry. RESULTS: Before intervention, when compared with those in the control group, the time of the first black stool defecation was prolonged (P<0.01, P<0.05), and numbers (P<0.01), wet weight (P<0.01, P<0.05) and water content (P<0.05, P<0.01) of stool in 6 h were reduced in the model, acupuncture, 3-MA and 3-MA + acupuncture groups. After intervention, compared with those in the control group, the time of the first black stool defecation was longer (P<0.05), and numbers (P<0.01), wet weight (P<0.01) and water content (P<0.01) of stool in 6 h were decreased in the model group. The time of the first black stool defecation was shortened (P<0.01), and numbers (P<0.01), wet weight (P<0.01) and water content (P<0.01) of stool in 6 h were increased in the acupuncture group when compared with those in the model group. The time of the first black stool defecation was extended (P<0.01), and numbers (P<0.01), wet weight (P<0.01) and water content (P<0.01) of stool in 6 h were declined in the 3-MA + acupuncture group in comparison with those in the acupuncture group. All layers of colon tissue were normal and intact in each group. When compared with the control group, the small intestine propulsion rate and the average optical density (OD) values of LC3, Beclin-1 and NeuN in neurons of colonic muscularis were decreased (P<0.01), and autophagosomes were dropped in the model group. In the acupuncture group, the small intestine propulsion rate and the average OD values of NeuN, LC3 and Beclin-1 in neurons of colonic muscularis increased (P<0.01,P<0.05), and autophagosomes were elevated when compared with those in the model group. The small intestine propulsion rate and the average OD values of NeuN, LC3 and Beclin-1 in neurons of colonic muscularis were dropped (P<0.05,P<0.01) in the 3-MA + acupuncture group in comparison with those in the acupuncture group. CONCLUSIONS: Electroacupuncture may promote enteric neuronal autophagy and increase the number of neurons so that the intestinal motility can be improved and constipation symptoms can be relieved in FC mice.


Asunto(s)
Electroacupuntura , Ratones , Animales , Beclina-1 , Puntos de Acupuntura , Estreñimiento/terapia , Intestino Delgado , Autofagia , Agua
18.
Artículo en Inglés | MEDLINE | ID: mdl-37988205

RESUMEN

An autonomous underwater vehicle (AUV) has shown impressive potential and promising exploitation prospects in numerous marine missions. Among its various applications, the most essential prerequisite is path planning. Although considerable endeavors have been made, there are several limitations. A complete and realistic ocean simulation environment is critically needed. As most of the existing methods are based on mathematical models, they suffer from a large gap with reality. At the same time, the dynamic and unknown environment places high demands on robustness and generalization. In order to overcome these limitations, we propose an information-assisted reinforcement learning path planning scheme. First, it performs numerical modeling based on real ocean current observations to establish a complete simulation environment with the grid method, including 3-D terrain, dynamic currents, local information, and so on. Next, we propose an information compression (IC) scheme to trim the mutual information (MI) between reinforcement learning neural network layers to improve generalization. A proof based on information theory provides solid support for this. Moreover, for the dynamic characteristics of the marine environment, we elaborately design a confidence evaluator (CE), which evaluates the correlation between two adjacent frames of ocean currents to provide confidence for the action. The performance of our method has been evaluated and proven by numerical results, which demonstrate a fair sensitivity to ocean currents and high robustness and generalization to cope with the dynamic and unknown underwater environment.

19.
Artículo en Inglés | MEDLINE | ID: mdl-37903037

RESUMEN

In the decade, artificial intelligence has achieved great popularity and applications in medicine and healthcare. Various AI-based algorithms have shown astonishing performance. However, in various data-driven smart healthcare algorithms, the problem of incomplete dataset remains a huge challenge. In this paper, we propose a data completeness enhancement algorithm based on generative AI (i.e., GenAI-DAA) to solve the problems of the in-sufficient data for model training, the data imbalance, and the biases of the training samples. We first construct the cognitive field of the generative models and effectively understand the state of incomplete cognition in generative models. Secondly, on this basis, we propose a quest algorithm for abnormal samples in the cognitive field based on local outlier factor. By fine-grained value evaluation, abnormal samples are given more refined attention. Finally, integrating the above process through multiple cognitive adjustments, GenAI-DAA gradually improves the cognitive ability. GenAI-DAA can be summarized as "Quest-→Estimate-→Tune-up". We have conducted extensive experiments to demonstrate the effectiveness of our proposed algorithm, and shown widely applications to some typical data-driven smart healthcare algorithms.

20.
RSC Adv ; 13(35): 24628-24638, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37601589

RESUMEN

Acetylene hydrogenation is a well-accepted solution to reduce by-products in the ethylene production process, while one of the key technical difficulties lies in developing a catalyst that can provide highly dispersed active sites. In this work, a highly crystalline layered covalent organic framework (COF) material (TbBpy) with excellent thermal stability was synthesized and firstly applied as support for ultrasmall Pd nanoparticles to catalyze acetylene hydrogenation. 100% of C2H2 conversion and 88.2% of C2H4 selectivity can be obtained at 120 °C with the space velocity of 70 000 h-1. The reaction mechanism was elucidated by applying a series of characterization techniques and theoretical calculation. The results indicate that the coordination between Pd and N atom in the bipyridine functional groups of COFs successfully increased the dispersibility and stability of Pd particles, and the introduction of COFs not only improved the adsorption of acetylene and H2 onto catalyst surface, but enhanced the electron transfer process, which can be responsible for the high selectivity and activity of catalyst. This work, for the first time, reported the excellent performance of Pd@TbBpy as a catalyst for acetylene hydrogenation and will facilitate the development and application of COFs materials in the area of petrochemicals.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA