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1.
J Am Chem Soc ; 146(29): 20193-20204, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39004825

ABSTRACT

High-entropy intermetallic (HEI) nanocrystals, composed of multiple elements with an ordered structure, are of immense interest in heterogeneous catalysis due to their unique geometric and electronic structures and the cocktail effect. Despite tremendous efforts dedicated to regulating the metal composition and structures with advanced synthetic methodologies to improve the performance, the surface structure, and local chemical order of HEI and their correlation with activity at the atomic level remain obscure yet challenging. Herein, by determining the three-dimensional (3D) atomic structure of quinary PdFeCoNiCu (PdM) HEI using atomic-resolution electron tomography, we reveal that the local chemical order of HEI regulates the surface electronic structures, which further mediates the alkyl-substitution-dependent alkyne semihydrogenation. The 3D structures of HEI PdM nanocrystals feature an ordered (intermetallic) core enclosed by a disordered (solid-solution) shell rather than an ordered surface. The lattice mismatch between the core and shell results in apparent near-surface distortion. The chemical order of the intermetallic core increases with annealing temperature, driving the electron redistribution between Pd and M at the surface, but the surface geometrical (chemically disordered) configurations and compositions are essentially unchanged. We investigate the catalytic performance of HEI PdM with different local chemical orders toward semihydrogenation across a broad range of alkynes, finding that the electron density of surface Pd and the hindrance effect of alkyl substitutions on alkynes are two key factors regulating selective semihydrogenation. We anticipate that these findings on surface atomic structure will clarify the controversy regarding the geometric and/or electronic effects of HEI catalysts and inspire future studies on tuning local chemical order and surface engineering toward enhanced catalysts.

2.
Nat Mater ; 22(8): 1007-1012, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37349394

ABSTRACT

Experimental mapping of transmission is essential for understanding and controlling charge transport through molecular devices and materials. Here we developed a single-molecule photoelectron tunnelling spectroscopy approach for mapping transmission beyond the HOMO-LUMO gap of the single diketopyrrolopyrrole molecule junction using an ultrafast-laser combined scanning tunnelling microscope-based break junction set-up at room temperature. Two resonant transport channels of ultrafast photocurrent are found by our photoelectron tunnelling spectroscopy, ranging from 1.31 eV to 1.77 eV, consistent with the LUMO + 1 and LUMO + 2 in the transmission spectrum obtained by density functional theory calculations. Moreover, we observed the modulation of resonant peaks by varying bias voltages, which demonstrates the ability to quantitatively characterize the effect of the electric field on frontier molecular orbitals. Our single-molecule photoelectron tunnelling spectroscopy offers an avenue that allows us to explore the nature of energy-dependent charge transport through single-molecule junctions.

3.
Langmuir ; 40(1): 853-859, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38146180

ABSTRACT

Precision manipulation of various liquids is essential in many fields such as various thermal, optical, and medical applications. This paper proposes an effective noncontact microdroplet separation method that is based on the action of corona discharge. A blade-plate electrode is constructed to generate an ionic wind, thereby enabling the droplet to be separated according to the shape of the blade electrode. Line, curve, S-shape, and parallel separation of the droplet can be realized in the experiment setup. Furthermore, experiment parameters, including the driving voltage, cutting speed, the distance of the upper and lower electrodes, cutting depth, etc., are discussed. Experimental results show that the proposed method is feasible and effective and can be used in application scenarios that require precise manipulation of droplets.

4.
Langmuir ; 39(44): 15636-15642, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37877665

ABSTRACT

Liquid deformation and motion are very common natural phenomena and of great value in various practical applications. In this study, a dielectric fluid column formation and directional flow phenomenon are presented. Dielectric fluid can grow upward to form a liquid column through a spatial electric field and realize directional and controllable operation of the liquid column by regulating spatial electric field distribution. First, the adjustable electric field space is constructed by connecting the two parallel electrodes to the high-voltage DC power supply. Then, the regional electric field distribution was adjusted by the upper plate graphic and power supply regulation to drive the polymer liquid on the lower plate electrode to form a liquid column at different positions. The results show that the polymer liquid column can be driven by the spatial electric field distributed dynamic control method and that the height and the narrowest width of the liquid column are directly controlled by the voltage. With the experiment conditions that the distance between two parallel electrodes is 5-15 mm, the formation of liquid columns with a height of 5-15 mm can be controlled. In addition, the liquid column can be driven by adjusting the on-states of different conductive regions. When the voltage is 10 kV, the liquid column directional movement speed can reach 1 mm/s. The higher the voltage, the faster the directional movement. The research results can be used as producing polydimethylsiloxane stamp, localized heating and temperature control, fabricating a pulsating heat pipe, and so on.

5.
Angew Chem Int Ed Engl ; 62(19): e202302693, 2023 May 02.
Article in English | MEDLINE | ID: mdl-36896843

ABSTRACT

The charge transport through single-molecule electronic devices can be controlled mechanically by changing the molecular geometrical configuration in situ, but the tunable conductance range is typically less than two orders of magnitude. Herein, we proposed a new mechanical tuning strategy to control the charge transport through the single-molecule junctions via switching quantum interference patterns. By designing molecules with multiple anchoring groups, we switched the electron transport between the constructive quantum interference (CQI) pathway and the destructive quantum interference (DQI) pathway, and more than four orders of magnitude conductance variation can be achieved by shifting the electrodes in a range of about 0.6 nm, which is the highest conductance range ever achieved using mechanical tuning.

6.
Sensors (Basel) ; 22(22)2022 Nov 20.
Article in English | MEDLINE | ID: mdl-36433573

ABSTRACT

The objective of the proposed human-machine cooperation (HMC) workstation is to both rapidly detect calcium-based fish bones in masses of minced fish floss and visually guide operators in approaching and removing the detected fish bones by hand based on the detection of fingernails or plastic-based gloves. Because vibration is a separation mechanism that can prevent absorption or scattering in thick fish floss for UV fluorescence detection, the design of the HMC workstation included a vibration unit together with an optical box and display screens. The system was tested with commonly used fish (swordfish, salmon, tuna, and cod) representing various cooking conditions (raw meat, steam-cooked meat, and fish floss), their bones, and contaminating materials such as derived from gloves made of various types of plastic (polyvinylchloride, emulsion, and rubber) commonly used in the removal of fish bones. These aspects were each investigated using the spectrum analyzer and the optical box to obtain and analyze the fluorescence spectra and images. The filter was mounted on a charge-coupled device, and its transmission-wavelength window was based on the characteristic band for fish bones observed in the spectra. Gray-level AI algorithm was utilized to generate white marker rectangles. The vibration unit supports two mechanisms of air and downstream separation to improve the imaging screening of fish bones inside the considerable flow of fish floss. Notably, under 310 nm ultraviolet B (UVB) excitation, the fluorescence peaks of the raw fillets, steam-cooked meat, and fish floss were observed at for bands at longer wavelengths (500-600 nm), whereas those of the calcium and plastic materials occurred in shorter wavelength bands (400-500 nm). Perfect accuracy of 100% was achieved with the detection of 20 fish bones in 2 kg of fish floss, and the long test time of around 10-12 min results from the manual removal of these fish bones.


Subject(s)
Calcium , Vibration , Animals , Humans , Fluorescence , Steam , Fishes , Technology , Plastics
7.
Cutan Ocul Toxicol ; 41(1): 43-48, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34844494

ABSTRACT

Glaucoma is a neurodegenerative disease that leads to irrevocable blindness. In glaucoma, even though axonal damage and function deficit culminates in retinal ganglion cell (RGC) degeneration, our knowledge on the autophagic mechanisms and the role of specific microRNAs is still limited. In this study, we investigated the role of microRNA-124 (MiR-124) in surgically induced glaucomatous neurodegeneration using a mouse model. Animals were segregated into four cohorts of 10 each: (i) sham-operated (n = 10); (ii) surgically induced glaucoma (SIG; n = 10); (iii) SIG + miR-124 mimic; (iv) SIG + miR-NC. Chronic elevation of intraocular pressure (IOP) is a critical risk factor for glaucoma. In our study, chronically elevated IOP caused anterograde axonal transport (AAT) defect, increased the autophagic activity (manifested by significantly (p < 0.05) increased LC3-II/LC3-I ratio, beclin-1 and Atg7 protein expressions) and also downmodulated the protein expression of p-Akt and p-mTOR, mediated by the purinergic P2 receptor subtype 7 (P2X7) upmodulation-leading to retinal degeneration. However, administration of miR-124 mimic improved the retinal integrity and function, as indicated by the improved AAT function, normalized the autophagic dysfunction, modulated the protein expression of P2X7-mediated p-Akt and p-mTOR. Hence, we propose that development of miR-124-based advanced therapies might be a potential avenue in the treatment of glaucomatous neurodegeneration.


Subject(s)
Glaucoma , MicroRNAs , Neurodegenerative Diseases , Animals , Disease Models, Animal , Glaucoma/genetics , Glaucoma/metabolism , Intraocular Pressure , Mice , MicroRNAs/genetics , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases
8.
Cent Eur J Immunol ; 47(1): 20-29, 2022.
Article in English | MEDLINE | ID: mdl-35600154

ABSTRACT

The protective activity of scopoletin (SPT) against glucose-induced cataract has been attributed to attenuation of aldose reductase activity and oxidative stress in a rat model. The present investigation was aimed to study the protective effect and mechanism of SPT in retinal ganglia cells (RGC) under oxidative stress and apoptosis induced by hyperglycemia. The RGC-5 cells were pre-conditioned with variable SPT concentrations for 6 hours and then subjected to hyperglycemia for 48 hours. The cell viability, mito- chondrial membrane potential (MMP) and oxidative stress markers were quantified. Western blotting was employed to screen the expression of mitogen-activated protein kinase (MAPK) and various apoptosis related proteins. SPT blocked the high-glucose induced cell injury and normalized the mitochondrial functioning via lowering the loss of MMP and release of cytochrome c. Pretreatment with SPT suppressed the enhanced ROS, malondialdehyde, and protein carbonyl content triggered by high-glucose exposure in RGC-5 cells. SPT normalized the apoptotic proteins in RGC-5 cells. The phosphorylation of c-Jun N-terminal kinases (JNK) and p38 MAPK in RGC-5 due to hyperglycemia was attenuated by SPT. Overall, SPT exhibited a protective effect in RGC-5 cells exposed to a high-glucose environment via its antioxidant efficacy, inhibition of apoptosis and modulation of the ROS-dependent p38/JNK signaling cascade.

9.
Org Biomol Chem ; 19(16): 3601-3610, 2021 04 28.
Article in English | MEDLINE | ID: mdl-33908578

ABSTRACT

The zinc salt-catalyzed reduction of α-aryl imino esters, diketones and phenylacetylenes with water as hydrogen source and zinc as reductant was successfully conducted. The presented method provides a low-cost, environmentally friendly and practical preparation of α-aryl amino esters, α-hydroxyketones and phenylethylenes. By using D2O as deuterium source, the corresponding products were obtained in high efficiency with excellent deuterium incorporation rate, which gives a cheap and safe tool for access to valuable deuterium-labelled compounds.

10.
Exp Cell Res ; 396(1): 112265, 2020 11 01.
Article in English | MEDLINE | ID: mdl-32898553

ABSTRACT

Many bone diseases result from abnormal bone resorption by osteoclasts (OCs). Studying OC related regulatory genes is necessary for the development of new therapeutic strategies. Rho GTPases have been proven to regulate OC differentiation and function and only mature OCs can carry out bone resorption. Here we demonstrate that Rac1 and Cdc42 exchange factor Triple functional domain (Trio) is critical for bone resorption caused by OCs. In this study, we created LysM-Cre;Triofl/fl conditional knockout mice in which Trio was conditionally ablated in monocytes. LysM-Cre;Triofl/fl mice showed increased bone mass due to impaired bone resorption caused by OCs. Furthermore, our in vitro analysis indicated that Trio conditional deficiency significantly suppressed OC differentiation and function. At the molecular level, Trio deficiency significantly inhibited the expression of genes critical for osteoclastogenesis and OC function. Mechanistically, our researches suggested that perturbed Rac1/Cdc42-PAK1-ERK/p38 signaling could be used to explain the lower ability of bone resorption in CKO mice. Taken together, this study indicates that Trio is a regulator of OCs. Studying the role of Trio in OCs provides a potential new insight for the treatment of OC related bone diseases.


Subject(s)
Bone Resorption/genetics , Femur/metabolism , Guanine Nucleotide Exchange Factors/genetics , Neuropeptides/genetics , Osteoclasts/metabolism , Phosphoproteins/genetics , Protein Serine-Threonine Kinases/genetics , cdc42 GTP-Binding Protein/genetics , rac1 GTP-Binding Protein/genetics , Animals , Bone Resorption/metabolism , Bone Resorption/pathology , Cell Differentiation/drug effects , Female , Femur/cytology , Femur/drug effects , Gene Expression Regulation , Guanine Nucleotide Exchange Factors/deficiency , Macrophage Colony-Stimulating Factor/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Monocytes/cytology , Monocytes/drug effects , Monocytes/metabolism , Neuropeptides/metabolism , Osteoclasts/cytology , Osteoclasts/drug effects , Osteogenesis/drug effects , Osteogenesis/genetics , Phosphoproteins/deficiency , Protein Serine-Threonine Kinases/deficiency , RANK Ligand/pharmacology , Signal Transduction , cdc42 GTP-Binding Protein/metabolism , p38 Mitogen-Activated Protein Kinases/genetics , p38 Mitogen-Activated Protein Kinases/metabolism , rac1 GTP-Binding Protein/metabolism
11.
Bull Environ Contam Toxicol ; 107(4): 616-625, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33175187

ABSTRACT

Ocean acidification and microplastic pollution is a global environmental threat, this research evaluated the effects of ocean acidification and microplastics on mussel digestive tract microbial community. The 16S rRNA gene was sequenced to characterize the flora. Species diversity in the samples was assessed by clustering valid tags on 97% similarity. Bacteroidetes, Firmicutes and Proteobacteria were the three most abundant genera in the four groups, with Bacteroidetes showing the highest diversity. However, no differences in flora structure were evident under various treatments. Phylogenetic relationship analysis revealed Bacteroidetes and Firmicutes had the highest OTU diversity. The weighted UniFrac distance, principal coordinate analysis (PCoA), unweighted pair group method with arithmetic mean (UPGMA) cluster tree and analysis of molecular variance (AMOVA) evaluation results for all samples also showed that changes in pH and microplastics concentration did not significantly affect the microbial community structure in the mussel digestive tract. The results presented the no significant effects of ocean acidification and microplastics intake on mussel intestinal diversity.


Subject(s)
Mytilus , Animals , Hydrogen-Ion Concentration , Intestines , Microplastics , Oceans and Seas , Phylogeny , Plastics , RNA, Ribosomal, 16S/genetics , Seawater
12.
Phys Chem Chem Phys ; 22(7): 4115-4121, 2020 Feb 19.
Article in English | MEDLINE | ID: mdl-32031551

ABSTRACT

The aerogen bond between the Xe and chalcogen atoms in complexes pairing XeOF2 with R1YR2 is examined by ab initio calculations for Y = O, S, and Se. In addition to HYH, one or both H atoms are changed to F or methyl groups. The interaction energies are strong, varying between 21 and 54 kJ mol-1. The aerogen bond is composed of roughly half electrostatic attraction, with lesser contributions due to polarization and dispersion. Replacement of H by electron-withdrawing F on the base weakens the interaction, while electron releasing Me substituents have the opposite effect. Whereas the aerogen bonds are stronger for O than for S or Se for HYH, HYF, and MeYH, it is the heavier chalcogen atoms that form the stronger dimers for MeOF and MeOMe. These trends cannot be fully explained by molecular electrostatic potentials or by measures of charge transfer, nor are they entirely consistent with electron density topology.

13.
Curr Microbiol ; 77(8): 1890-1895, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32356168

ABSTRACT

In this study, a wild-type Pseudomonas aeruginosa strain KT1115 with the capability of converting rapeseed oils into di-rhamnolipids, a class of biosurfactants with extensive application potential, was successfully isolated and characterized. Di-rhamnolipids production by microorganism culture provided a mild, eco-friendly, and secure approach for surfactants production instead of conventional chemical synthesis. However, few studies have been attempted to explore the metabolic mechanism behind the high di-rhamnolipids production by P. aeruginosa. Here, we presented the graft genome of a wild-type P. aeruginosa strain KT1115, with emphasis on the analysis of oils metabolism and rhamnolipid synthesis. The availability of the genome sequence provides additional insight into the genetic mechanism enhancing di-rhamnolipids biosynthesis.


Subject(s)
Genome, Bacterial , Glycolipids/biosynthesis , Metabolic Networks and Pathways/genetics , Pseudomonas aeruginosa/genetics , Rapeseed Oil/metabolism , Pseudomonas aeruginosa/metabolism , Surface-Active Agents/metabolism
14.
Sensors (Basel) ; 20(6)2020 Mar 12.
Article in English | MEDLINE | ID: mdl-32178238

ABSTRACT

LiDAR sensors can provide dependable 3D spatial information at a low frequency (around 10 Hz) and have been widely applied in the field of autonomous driving and unmanned aerial vehicle (UAV). However, the camera with a higher frequency (around 20 Hz) has to be decreased so as to match with LiDAR in a multi-sensor system. In this paper, we propose a novel Pseudo-LiDAR interpolation network (PLIN) to increase the frequency of LiDAR sensor data. PLIN can generate temporally and spatially high-quality point cloud sequences to match the high frequency of cameras. To achieve this goal, we design a coarse interpolation stage guided by consecutive sparse depth maps and motion relationship. We also propose a refined interpolation stage guided by the realistic scene. Using this coarse-to-fine cascade structure, our method can progressively perceive multi-modal information and generate accurate intermediate point clouds. To the best of our knowledge, this is the first deep framework for Pseudo-LiDAR point cloud interpolation, which shows appealing applications in navigation systems equipped with LiDAR and cameras. Experimental results demonstrate that PLIN achieves promising performance on the KITTI dataset, significantly outperforming the traditional interpolation method and the state-of-the-art video interpolation technique.

15.
Sensors (Basel) ; 20(12)2020 Jun 19.
Article in English | MEDLINE | ID: mdl-32575436

ABSTRACT

The research of robotic autonomous radioactivity detection or radioactive source search plays an important role in the monitoring and disposal of nuclear safety and biological safety. In this paper, a method for autonomously searching for radioactive sources through mobile robots was proposed. In the method, by using a partially observable Markov decision process (POMDP), the search of autonomous unknown radioactive sources was realized according to a series of radiation information measured by mobile robot. First, the factors affecting the accuracy of radiation measurement during the robot's movement were analyzed. Based on these factors, the behavior set of POMDP was designed. Secondly, the parameters of the radioactive source were estimated in the Bayesian framework. In addition, through the reward strategy, autonomous navigation of the robot to the position of the radiation source was achieved. The search algorithm was simulated and tested, and the TurtleBot robot platform was used to conduct a real search experiment on the radio source Cs-137 with an activity of 37 MBq indoors. The experimental results showed the effectiveness of the method. Additionally, from the experiments, it could been seen that the robot was affected by the linear velocity, angular velocity, positioning accuracy and the number of measurements in the process of autonomous search for the radioactive source. The proposed mobile robot autonomous search method can be applied to the search for lost radioactive sources, as well as for the leakage of substances (nuclear or chemical) in nuclear power plants and chemical plants.

16.
Med Sci Monit ; 25: 1113-1121, 2019 Feb 11.
Article in English | MEDLINE | ID: mdl-30739905

ABSTRACT

BACKGROUND Diabetic retinopathy (DR) is a macrovascular complication that occurs in diabetic patients. Conventional treatments for the management of DR have many limitations. Thus, the present investigation evaluated the protective effect of fangchinoline against diabetic retinopathy (DR). MATERIAL AND METHODS DR was induced by streptozotocin (STZ; 60 mg/kg; i.p.) and rats were treated with fangchinoline 1, 3, and 10 mg/kg for 16 weeks. DR was confirmed by determining the concentration of advanced glycation end-products (AGEs) and morphology of retinal tissues. Parameters of oxidative stress and expression of inflammatory cytokines and receptor for advanced glycation end-products (RAGE) in the retinal tissue were determined by Western blot assay and reverse transcription polymerase chain reaction (RT-PCR). Moreover enzyme-linked immunosorbent assay (ELISA) was used to determine the apoptosis index and activity of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the retinal tissues. RESULTS Our study reveals that the concentration of glycosylated hemoglobin (HbA1c) and glucose in the plasma and AGEs in the retinal tissue were significantly reduced in the fangchinoline group compared to the DR group. Moreover, treatment with fangchinoline attenuated the altered retinal morphology and expression of inflammatory mediators and RAGE in the retinal tissues of DR rats. There was a significant (p<0.01) decrease in oxidative stress, activity of NF-κB, and apoptosis index in the fangchinoline group compared to the DR group of rats. CONCLUSIONS Our investigation shows that fangchinoline attenuates the apoptosis of retinal cells in STZ-induced diabetic retinopathy rats by inhibiting the RAGE/NF-κB pathway.


Subject(s)
Benzylisoquinolines/pharmacology , Diabetic Retinopathy/drug therapy , Animals , Apoptosis/drug effects , Benzylisoquinolines/therapeutic use , Cytokines , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/drug therapy , Glycated Hemoglobin , Male , NF-kappa B/drug effects , Oxidative Stress , Rats , Rats, Wistar , Receptor for Advanced Glycation End Products/drug effects , Retina , Signal Transduction
17.
BMC Complement Altern Med ; 17(1): 531, 2017 Dec 13.
Article in English | MEDLINE | ID: mdl-29237430

ABSTRACT

BACKGROUND: Quercetin (QCT) is a flavonol present in many vegetables, it is proved to show chemo preventive effect against lung, cervical, prostate, breast and colon cancer due to its anti-inflammatory, anti-tumor and anti-oxidant property. Looking into the reported chemo-preventive effect we speculated antitumor activity in retinoblastoma (RB) Y79 cells, we also studied the molecular mechanism for antitumor activity. METHODS: The effect of QCT on Y79 cell viability count was done by cell counting kit, cell cycle distribution, apoptosis studies and mitochondrial membrane potential was evaluated by flow cytometry. Protein expression was done by western blot analysis. RESULTS: The outcomes of study showed that QCT reduced Y79 cell viability and caused arrest of G1 phase in cell cycle via decreasing the expression levels of cyclin-dependent kinase (CDK)2/6 and cyclin D3 and by increasing the levels of both CDK inhibitor proteins p21 and p27. Apoptosis of Y79 cells mediated by QCT occurred via activation of both caspases-3/-9. Flow cytometry studies showed that QCT caused collapse in mitochondrial membrane potential (ΔΨm) in Y79 cells. Western blot studies confirmed that QCT brought about phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). We also established that inhibitors of JNK and p38 MAPK suppressed QCT mediated activation of both caspases-3/-9 and subdued the apoptosis of cancerous Y79 cells. CONCLUSION: All the results of the study suggest that QCT induced the apoptosis of Y79 cells via activation of JNK and p38 MAPK pathways, providing a novel treatment approach for human RB.


Subject(s)
Antineoplastic Agents/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , MAP Kinase Signaling System/drug effects , Quercetin/pharmacology , Retinoblastoma/metabolism , Apoptosis/drug effects , Cell Line, Tumor , Humans
18.
J Environ Qual ; 46(5): 1106-1113, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28991978

ABSTRACT

There is a limited understanding of solute transport properties of degraded peat soils as compared to mineral substrates. A lower organic matter (OM) content is often the result of peat degradation and mineralization following artificial drainage. In this study, we aimed at deducing changes in solute transport properties of peat soils differing in OM content. Miscible displacement experiments were conducted on 70 undisturbed soil columns with OM contents ranging from 11 to 86% w/w under saturated steady-state conditions using tritium and bromide as conservative tracers. Measured breakthrough curves (BTCs) were subjected to model analysis using three different approaches: single-porosity model (SPM), mobile-immobile model (MIM), and two-flow region model (TFRM). The results indicated that (i) nonequilibrium solute transport processes are common in peat soils; (ii) the TFRM improved predictions of BTCs with heavy tailing or two peaks; (iii) applied tracers, tritium and bromide, were retarded in peat soils with higher OM content; and (iv) pronounced preferential flow mainly occurred in peat soils with lower OM content. This type of strong preferential flow had a small ratio of measured to fitted pore water velocity and a greater ratio of velocities (/ > 3.0) in the fast and slow transport region as obtained from the TFRM. We conclude that shallow groundwater resources are more likely to become polluted in drained and degraded fen peats that are used for agricultural purposes.


Subject(s)
Groundwater/chemistry , Soil/chemistry , Models, Theoretical , Soil Pollutants , Water Movements
19.
Front Bioeng Biotechnol ; 12: 1358022, 2024.
Article in English | MEDLINE | ID: mdl-38344287

ABSTRACT

In recent years, lower limb exoskeletons have achieved satisfactory clinical curative effects in rehabilitating stroke patients. Furthermore, generating individualized trajectories for each patient and avoiding secondary injury in rehabilitation training are important issues. This paper explores the utilization of series elastic actuator (SEA) to deliver compliant force and enhance impact resistance in human-robot interaction, and we present the design of novel knee exoskeleton driven by SEA. Subsequently, the novel gait trajectory prediction method and compliant control method are proposed. The attention-based CNN-LSTM model is established to generate personalized gait trajectories for affected limbs, in which the spatial-temporal attention mechanism is adopted to improve the prediction accuracy. The compliant control strategy is proposed to nonlinearly and adaptively tune impedance parameters based on artificial potential field (APF) method, and active rehabilitation training is carried out in the coordination space to guarantee patient safety. The experimental results based on four healthy subjects demonstrated that synergetic gait prediction model could satisfactorily characterize the coordination movement with higher accuracy. The compliant control could limit the patient's movement in the safe coordination tunnel while considering personalization and flexibility.

20.
Sci Rep ; 14(1): 1047, 2024 01 10.
Article in English | MEDLINE | ID: mdl-38200098

ABSTRACT

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common congenital facial malformation with a complex, incompletely understood origin. Long noncoding RNAs (lncRNAs) have emerged as pivotal regulators of gene expression, potentially shedding light on NSCL/P's etiology. This study aimed to identify critical lncRNAs and construct regulatory networks to unveil NSCL/P's underlying molecular mechanisms. Integrating gene expression profiles from the Gene Expression Omnibus (GEO) database, we pinpointed 30 dysregulated NSCL/P-associated lncRNAs. Subsequent analyses enabled the creation of competing endogenous RNA (ceRNA) networks, lncRNA-RNA binding protein (RBP) interaction networks, and lncRNA cis and trans regulation networks. RT-qPCR was used to examine the regulatory networks of lncRNA in vivo and in vitro. Furthermore, protein levels of lncRNA target genes were validated in human NSCL/P tissue samples and murine palatal shelves. Consequently, two lncRNAs and three mRNAs: FENDRR (log2FC = - 0.671, P = 0.040), TPT1-AS1 (log2FC = 0.854, P = 0.003), EIF3H (log2FC = - 1.081, P = 0.041), RBBP6 (log2FC = 0.914, P = 0.037), and SRSF1 (log2FC = 0.763, P = 0.026) emerged as potential contributors to NSCL/P pathogenesis. Functional enrichment analyses illuminated the biological functions and pathways associated with these lncRNA-related networks in NSCL/P. In summary, this study comprehensively delineates the dysregulated transcriptional landscape, identifies associated lncRNAs, and reveals pivotal sub-networks relevant to NSCL/P development, aiding our understanding of its molecular progression and setting the stage for further exploration of lncRNA and mRNA regulation in NSCL/P.


Subject(s)
Cleft Lip , Cleft Palate , RNA, Long Noncoding , Humans , Animals , Mice , Cleft Palate/genetics , Cleft Lip/genetics , RNA, Long Noncoding/genetics , Databases, Factual , Hydrolases , RNA, Messenger/genetics , DNA-Binding Proteins , Ubiquitin-Protein Ligases , Serine-Arginine Splicing Factors
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