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1.
Food Chem X ; 21: 101247, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38434695

ABSTRACT

The assessment of total antioxidant capacity (TAC) is crucial for evaluating overall antioxidant potential, predicting the risk of chronic diseases, guiding dietary and nutritional interventions, and studying the effectiveness of antioxidants. However, achieving rapid TAC assessment with high sensitivity and stability remains a challenge. In this study, Ce/Fe-MOF with abundant oxygen vacancies was synthesized using microplasma for TAC determination. The microplasma synthesis method was rapid (30 min) and cost-effective. The presence of oxygen vacancies and the collaboration between iron and cerium in Ce/Fe-MOF not only enhanced the catalyst's efficiency but also conferred multiple enzyme-like properties: peroxidase-like, oxidase-like, and superoxide dismutase mimetic activities. Consequently, a simple colorimetric assay was established for TAC determination in vegetables and fruits, featuring a short analysis time of 15 min, a good linear range of 5-60 µM, a low detection limit of 1.3 µM and a good recovery of 91 %-107 %. This method holds promise for rapid TAC assessment in agricultural products.

2.
Huan Jing Ke Xue ; 44(1): 367-375, 2023 Jan 08.
Article in Chinese | MEDLINE | ID: mdl-36635824

ABSTRACT

Copper smelting can cause heavy metal pollution in surrounding soil and threaten human health. This study examined the characteristics, distribution, and health risk of heavy metals in soil with different land uses around 40 copper smelting sites at home and abroad by collecting published literature data. The results showed that the mean values of ω(As), ω(Cd), ω(Cu), ω(Pb), and ω(Zn) in the soil around the copper smelting sites were 196, 10.5, 1948, 604, and 853 mg·kg-1, respectively. The order of Igeo was Cd(5.63)>Cu(3.88)>As(2.96)>Pb(2.30)>Zn(1.27), and the accumulation of Cd and Cu was the most serious. High Nemero index (NIPI) values were found in the soil around smelting sites with a long history of smelting, outdated process, and insufficient environmental protection measures. Significant correlations were found between the concentrations of heavy metals in the soil, which decreased with the sampling distance. The heavy metals mainly accumulated within 2-3 km from the smelting sites. Compared with the smelting history, scale, and process, land use type had a lower effect on soil heavy metal concentrations. The heavy metals in the soil around copper smelters may pose carcinogenic and non-carcinogenic risks on residents. The high health risks were mainly caused by As and Pb in smelting production areas, and Pb in woodland. These results may guide the risk prevention of heavy metal pollution in the soil around smelting sites.


Subject(s)
Metals, Heavy , Soil Pollutants , Humans , Copper , Soil , Cadmium , Lead , Soil Pollutants/analysis , Environmental Monitoring , Metals, Heavy/analysis , Risk Assessment , China
3.
Angew Chem Int Ed Engl ; 61(44): e202211959, 2022 Nov 02.
Article in English | MEDLINE | ID: mdl-36109840

ABSTRACT

Covalent adaptable liquid crystal networks (CALCNs) are highly potential actuating materials due to their actuation properties and shape reprogrammability. Given the importance of network crosslinking state in a CALCN actuator, we sought an all-in-one strategy to probe and visualize its dynamic network while ensuring actuation and reprogramming. Here, tetraphenylethylene derivatives were incorporated into liquid crystal networks via the Diels-Alder (DA) reaction, acting simultaneously as reversible crosslinkers and aggregation-induced emission (AIE) fluorescent probes. The thermally tunable fluorescence of the resulting network can correlate to and thus visualize the actuator's crosslinking status, actuation capability and temperature in real-time and in situ, yielding an intriguing actuation limit-alerting function. Furthermore, we verified unprecedented reprogrammability of the AIE-type CALCNs through both associative and dissociative exchange mechanisms of DA chemistry.

4.
Soft Matter ; 18(26): 4850-4867, 2022 Jul 06.
Article in English | MEDLINE | ID: mdl-35730498

ABSTRACT

Soft actuators based on liquid crystal networks (LCNs) have aroused great scientific interest for use as stimuli-controlled shape-changing and moving components for robotic devices due to their fast, large, programmable and solvent-free actuation responses. Recently, various LCN actuators have been implemented in soft robotics using stimulus sources such as heat, light, humidity and chemical reactions. Among them, electrically driven LCN actuators allow easy modulation and programming of the input electrical signals (amplitude, phase, and frequency) as well as stimulation throughout the volume, rendering them promising actuators for practical applications. Herein, the progress of electrically driven LCN actuators regarding their construction, actuation mechanisms, actuation performance, actuation programmability and the design strategies for intelligent systems is elucidated. We also discuss new robotic functions and advanced actuation control. Finally, an outlook is provided, highlighting the research challenges faced with this type of actuator.

5.
Can J Gastroenterol Hepatol ; 2022: 8178184, 2022.
Article in English | MEDLINE | ID: mdl-35369117

ABSTRACT

A high Mandard score may indicate the tumor is insensitive to chemotherapy. We analyzed tumor regression and lymph node response under different Mandard scores to assess the impact of Mandard score on prognosis. Methods. Mandard scores and ypN stage of postoperative pathological reports were recorded. The results were reviewed by a professional pathologist. The radiologist compared the tumor regression before and after chemotherapy by computed tomography (CT). The survival of all patients was obtained by telephone follow-up. Multivariate Cox regression was used to assess the relationship between overall risk of death and Mandard score, imaging evaluation, and ypN stage. Results. In the Mandard score (4-5) group, the median survival time for PR and ypN0 patients was 68.5 and 76.7 months. While in the Mandard score (1-2) group, the median survival time for PD and ypN3a patients was 15.6 and 14.5 months. Imaging evaluation of tumor regression (PR 68.5 months, SD 27.8 months, and PD 10.2 months) and lymph node remission (ypN0 76.7 months, ypN1 61.6 months, ypN2 18.0 months, ypN3a 18.7 months, and ypN3b 18.3 months) showed improved survival. Mandard score, imaging evaluation, and ypN stage are important prognostic factors affecting prognosis. Conclusion. A high Mandard score does not mean neoadjuvant chemotherapy is ineffective in gastric cancer. Patients with imaging evaluation of tumor regression and ypN stage reduction may benefit from neoadjuvant chemotherapy.


Subject(s)
Neoadjuvant Therapy , Stomach Neoplasms , Humans , Lymph Nodes/diagnostic imaging , Lymph Nodes/pathology , Neoadjuvant Therapy/methods , Prognosis , Stomach Neoplasms/drug therapy , Stomach Neoplasms/pathology
6.
Huan Jing Ke Xue ; 42(8): 4015-4023, 2021 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-34309288

ABSTRACT

Vertically tiered soil profiles, comprising miscellaneous fill (S1), plain fill (S2), silty clay (S3), and completely weathered slate (S4), were collected from a zinc smelter site in Zhuzhou City, Hunan Province, and their Cd and Pb adsorption characteristics were examined. Static batch experiments were conducted with different initial Cd and Pb solution concentrations, at temperatures of 288-308 K and pH values of 2-6. The results showed that a pseudo first-order model could be fitted to the kinetics of Cd/Pb adsorption in these soils. The soil profiles had a large retention capacity for Cd and Pb. The Cd and Pb adsorption isotherms for these soils conformed to the Freundlich isotherm, with maximum adsorption at 298 K of 2097-4504 mg ·kg-1 for Cd and 4376-10564 mg ·kg-1 for Pb, based on the Langmuir isotherm. The adsorption capacity of Cd and Pb increased with an increase in initial pH and temperature. The Cd and Pb adsorption process were a spontaneous physical and chemical process, and the soil profiles were ranked by their Cd and Pb adsorption capacities in the following order:completely weathered slate (S4)>miscellaneous fill (S1)>silty clay (S3)>plain fill (S2). The variation in adsorption capacities resulted from the differences in physical and chemical properties of the soil, mainly Fe/Al content and cation exchange capacity. Fourier transform infrared and SEM-EDS analysis showed that the main adsorption mechanism is the exchange of Cd and Pb with Fe/Al, while -OH/C=O sites in soils were the predominant adsorption sites for Cd and Pb. In the study area, exogenous Cd and Pb discharged by smelting activity accumulated predominantly in surface soil, and their concentration gradually decreased with depth. These results provide a scientific basis for the prevention and control of heavy metal pollution in the soil and groundwater of a smelting site.


Subject(s)
Soil Pollutants , Soil , Adsorption , Cadmium/analysis , Cities , Hydrogen-Ion Concentration , Kinetics , Lead , Soil Pollutants/analysis , Zinc/analysis
7.
Nat Commun ; 12(1): 624, 2021 Jan 27.
Article in English | MEDLINE | ID: mdl-33504810

ABSTRACT

Liquid crystalline network (LCN) actuator normally deforms upon thermally or optically induced order-disorder phase transition, switching once between two shapes (shape 1 in LC phase and shape 2 in isotropic state) for each stimulation on/off cycle. Herein, we report an LCN actuator that deforms from shape 1 to shape 2 and then reverses the deformation direction to form shape 3 on heating or under light only, thus completing the shape switch twice for one stimulation on/off cycle. The deformation reversal capability is obtained with a monolithic LCN actuator whose two sides are made to start deforming at different temperatures and exerting different reversible strains, by means of asymmetrical crosslinking and/or asymmetrical stretching. This desynchronized actuation strategy offers possibilities in developing light-fueled LCN soft robots. In particular, the multi-stage bidirectional shape change enables multimodal, light-driven locomotion from the same LCN actuator by simply varying the light on/off times.

8.
ACS Macro Lett ; 10(6): 690-696, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-35549093

ABSTRACT

A chiral liquid crystalline elastomer (CLCE) actuator is demonstrated. The solution-cast polydomain film of CLCE can twist upon order-disorder phase transition without any preset alignment of mesogens. The handedness of twisting is specific to the molecular chirality of the chiral dopant in the CLCE structure, while the degree of twisting, in terms of helical pitch and diameter, is sensitive to the aspect ratio and the thickness of the CLCE strip as well as the chiral dopant content. This phenomenon appears to stem from the local twisting forces and deformations of randomly oriented helical domains, which cannot cancel each other out due to the chirality and thus result in a macroscopic "chiral" force acting on the CLCE actuator. This finding reveals a materials design for preparing twisting LCE actuators.

9.
Angew Chem Int Ed Engl ; 59(12): 4925-4931, 2020 Mar 16.
Article in English | MEDLINE | ID: mdl-31961040

ABSTRACT

Novel main-chain liquid crystalline Diels-Alder dynamic networks (LCDANs) were prepared that exhibit unprecedented ease for actuator programming and reprocessing compared to existing liquid crystalline network (LCN) systems. Following cooling from 125 °C, LCDANs are deformed with aligned mesogens self-locked at room temperature by slowly formed Diels-Alder (DA) bonds, which allows for the formation of solid 3D actuators capable of reversible shape change, and strip walker and wheel-capable light-driven locomotion upon either thermally or optically induced order-disorder phase transition. Any actuator can readily be erased at 125 °C and reprogrammed into a new one under ambient conditions. Moreover, LCDANs can be processed directly from melt (for example, fiber drawing) and from solution (for example, casting tubular actuators), which cannot be achieved with LCNs using exchangeable covalent bonds. The combined attributes of LCDANs offer significant progress toward developing easily programmable/processable LCN actuators.

10.
Math Biosci Eng ; 17(1): 179-201, 2019 09 30.
Article in English | MEDLINE | ID: mdl-31731346

ABSTRACT

In this paper, a mathematical model for microbial treatment in livestock and poultry sewage is proposed and analyzed. We consider periodic addition of microbial flocculants to treat microorganisms such as Escherichia coli in sewage. Different from the traditional models, a class of composite dynamics models composed of impulsive differential equations is established. Our aim is to study the relationship between substrate, microorganisms and flocculants in sewage systems as well as the treatment strategies of microorganisms. Precisely, we first show the process of mathematical modeling by using impulsive differential equations. Then by using the theory of impulsive differential equations, the dynamics of the model is investigated. Our results show that the system has a microorganismsextinction periodic solution which is globally asymptotically stable when a certain threshold value is less than one, and the system is permanent when a certain threshold value is greater than one. Furthermore, the control strategy for microorganisms treatment is discussed. Finally, some numerical simulations are carried out to illustrate the theoretical results.


Subject(s)
Sewage/microbiology , Wastewater/microbiology , Water Purification/methods , Animals , Computer Simulation , Escherichia coli , Flocculation , Livestock , Models, Biological , Oscillometry , Population Dynamics , Poultry
11.
Math Biosci Eng ; 16(5): 3807-3829, 2019 04 28.
Article in English | MEDLINE | ID: mdl-31499637

ABSTRACT

In this paper, a delayed phytoplankton-zooplankton system with the coeffcient depending on delay is investigated. Firstly, it gives the nonnegative and boundedness of solutions of the delay differential equations. Secondly, it gives the asymptotical stability properties of equilibria in the absence of time delay. Then in the presence of time delay, the existence of local Hopf bifurcation is discussed when the delay changes. In addition to that, the stability of periodic solution and bifurcation direction are also obtained through the use of central manifold theory. Furthermore, he global continuity of the local Hopf bifurcation is discussed by using the global Hopf bifurcation result of FDE. At last, some numerical simulations are presented to show the rationality of theoretical analyses.


Subject(s)
Phytoplankton/physiology , Zooplankton/physiology , Algorithms , Animals , Computer Simulation , Eutrophication , Models, Biological , Population Dynamics , Reproducibility of Results , Time Factors
12.
Adv Mater ; 31(36): e1903452, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31298439

ABSTRACT

Oriented liquid crystal networks (LCNs) can undergo reversible shape change at the macroscopic scale upon an order-disorder phase transition of the mesogens. This property is explored for developing soft robots that can move under external stimuli, such as light in most studies. Herein, electrically driven soft robots capable of executing various types of biomimetic locomotion are reported. The soft robots are composed of a uniaxially oriented LCN strip, a laminated Kapton layer, and thin resistive wires embedded in between. Taking advantage of the combined attributes of the actuator, namely, easy processing, reprogrammability, and reversible shape shift between two 3D shapes at electric power on and off state, the concept of a "Janus" soft robot is demonstrated, which is built from a single piece of the material and has two parts undergoing opposite deformations simultaneously under a uniform stimulation. In addition to complex shape morphing such as the movement of oarfish and sophisticated devices like self-locking grippers, electrically powered "Janus" soft robots can accomplish versatile locomotion modes, including crawling on flat surfaces through body arching up and straightening down, crawling inside tubes through body stretching and contraction, walking like four-leg animals, and human-like two-leg walking while pushing a load forward.

13.
Angew Chem Int Ed Engl ; 58(16): 5332-5337, 2019 Apr 08.
Article in English | MEDLINE | ID: mdl-30816599

ABSTRACT

The ability to optically reconfigure an existing actuator of a liquid crystal polymer network (LCN) so that it can display a new actuation behavior or function is highly desired in developing materials for soft robotics applications. Demonstrated here is a powerful approach relying on selective polymer chain decrosslinking in a LCN actuator with uniaxial LC alignment. Using an anthracene-containing LCN, spatially controlled optical decrosslinking can be realized through photocleavage of anthracene dimers under 254 nm UV light, which alters the distribution of actuation (crosslinked) and non-actuation (decrosslinked) domains and thus determines the actuation behavior upon order-disorder phase transitions. Based on this mechanism, a single actuator having a flat shape can be reconfigured in an on-demand manner to exhibit reversible shape transformation such as self-folding into origami three-dimensional structures. Moreover, using a dye-doped LCN actuator, a light-fueled microwalker can be optically reconfigured to adopt different locomotion behaviors, changing from moving in the laser scanning direction to moving in the opposite direction.

14.
Mol Biosyst ; 13(6): 1202-1212, 2017 May 30.
Article in English | MEDLINE | ID: mdl-28470244

ABSTRACT

In recent years, more and more studies have indicated that microRNAs (miRNAs) play critical roles in various complex human diseases and could be regarded as important biomarkers for cancer detection in early stages. Developing computational models to predict potential miRNA-disease associations has become a research hotspot for significant reduction of experimental time and cost. Considering the various disadvantages of previous computational models, we proposed a novel computational model based on super-disease and miRNA for potential miRNA-disease association prediction (SDMMDA) to predict potential miRNA-disease associations by integrating known associations, disease semantic similarity, miRNA functional similarity, and Gaussian interaction profile kernel similarity for diseases and miRNAs. SDMMDA could be applied to new diseases without any known associated miRNAs as well as new miRNAs without any known associated diseases. Due to the fact that there are very few known miRNA-disease associations and many associations are 'missing' in the known training dataset, we introduce the concepts of 'super-miRNA' and 'super-disease' to enhance the similarity measures of diseases and miRNAs. These super classes could help in including the missing associations and improving prediction accuracy. As a result, SDMMDA achieved reliable performance with AUCs of 0.9032, 0.8323, and 0.8970 in global leave-one-out cross validation, local leave-one-out cross validation, and 5-fold cross validation, respectively. In addition, esophageal neoplasms, breast neoplasms, and prostate neoplasms were taken as independent case studies, where 46, 43 and 48 out of the top 50 predicted miRNAs were successfully confirmed by recent experimental literature. It is anticipated that SDMMDA would be an important biological resource for experimental guidance.


Subject(s)
Computational Biology/methods , Computer Simulation , MicroRNAs/genetics , Algorithms , Genetic Association Studies , Genetic Predisposition to Disease/genetics
15.
ACS Appl Mater Interfaces ; 9(24): 20276-20293, 2017 Jun 21.
Article in English | MEDLINE | ID: mdl-28553712

ABSTRACT

Shape memory polymers (SMPs), with the capability to change from one or more temporary shapes to predetermined shapes in response to an external stimulus, have attracted much interest from both academia and industries. When introducing supramolecular interactions that have been featured as dynamic and reversible into the design of novel SMPs, intriguing and unique functionalities have been engendered and thereby broaden the potential applications of the SMPs to new territories. In this review, we summarize recent progress made in SMPs based on supramolecular interactions, provide insight into the material design and shape memory mechanism, elucidate and evaluate their properties and performance, and point out opportunities and applications of SMPs.

16.
Macromol Rapid Commun ; 38(14)2017 Jul.
Article in English | MEDLINE | ID: mdl-28544461

ABSTRACT

Moisture or water has the advantages of being green, inexpensive, and moderate. However, it is challenging to endow water-induced shape memory property and self-healing capability to one single polymer because of the conflicting structural requirement of the two types of materials. In this study, this problem is solved through introducing two kinds of supramolecular interactions into semi-interpenetrating polymer networks (semi-IPNs). The hydrogen bonds function as water-sensitive switches, making the materials show moisture-induced shape memory effect. The host-guest interactions (ß-cyclodextrin-adamantane) serve as both permanent phases and self-healing motifs, enabling further increased chain mobility at the cracks and self-healing function. In addition, these polyvinylpyrrolidone/poly(hydroxyethyl methacrylate-co-butyl acrylate) semi-IPNs also show thermosensitive triple-shape memory effect.


Subject(s)
Polymers/chemistry , Water/chemistry , Acrylates/chemistry , Adamantane/chemistry , Hydrogen Bonding , Povidone/chemistry , Temperature , beta-Cyclodextrins/chemistry
17.
Oncotarget ; 8(65): 108498-108508, 2017 Dec 12.
Article in English | MEDLINE | ID: mdl-29312546

ABSTRACT

Hepatocellular carcinoma (HCC) remains the third cause of cancer-related mortality. Resection and transplantation are the only curative treatments available but are greatly hampered by high recurrence rates and development of metastasis, the initiation of cancer metastasis requires migration and invasion of cells, which is enabled by epithelial-mesenchymal transitions (EMT). TGF-ß1 is a secreted protein that performs many cellular functions, including the control of cell growth, cell proliferation, cell differentiation and apoptosis. TGF-ß1 is known as a major inducer of EMT, and it was reported that TGF-ß1 induced EMT via Smad-dependent and Smad-independent pathways. However, the extrinsic signals of TGF-ß1 regulated the EMT in hepatoma cells remains to be elucidated, and searching drugs to inhibit TGF-ß1 induced EMT may be considered to be a potentially effective therapeutic strategy in HCC. Fortunately, in this study, we found that curcumin inhibited TGF-ß1-induced EMT in hepatoma cells. Furthermore, we demonstrated that curcumin inhibited TGF-ß1-induced EMT via inhibiting Smad2 phosphorylation and nuclear translocation, then suppressing Smad2 combined with the promoter of Snail which inhibited the transcriptional expression of Snail. These findings suggesting curcumin could be a useful agent for antitumor therapy and also a promising drug combined with other strategies to preventing and treating HCC.

18.
Sci Total Environ ; 576: 292-302, 2017 Jan 15.
Article in English | MEDLINE | ID: mdl-27788444

ABSTRACT

An orthogonal field experiment of giant reed (Arundo donax) modified with organic complex fertiliser (OCF), and OCF and fly ash (O&F), at different planting densities was carried out in metal-contaminated soil. The available percentage of arsenic (As) and lead (Pb) in soil decreased from 8.45% to 2.19% and from 29.6% to 13.5% by OCF, respectively, and that of cadmium (Cd) was reduced from 25.3% to 6.49% by O&F. The total biomass of giant reed was 631g per individual following application of O&F in contaminated soil. The accumulation of As, Cd, and Pb in giant reed was 1.57, 4.06, and 11.25mg per individual. Urease and sucrase activity were 87.4NH4-Nµg/gd and 63.1glucosemg/gd in response to the treatments modified using OCF, while the highest dehydrogenase activity was 101 TPF (triphenyltetrazolium formazan) µg/gd in the treatments modified using O&F. Dominant bacteria (frequency>50%) were enriched with increasing planting density of giant reed. These results indicate that the phytostabilisation of metal-contaminated soil by giant reed could be improved by the application of O&F or OCF.

19.
Chem Commun (Camb) ; 52(70): 10609-12, 2016 Aug 23.
Article in English | MEDLINE | ID: mdl-27366796

ABSTRACT

Light-, pH- and thermal-responsive hydrogels were prepared by introducing dansyl-aggregations and azo-cyclodextrin inclusion complexes as switches. The resulting material showed dual shape memory behavior in response to light, pH or temperature, respectively, and exhibits the triple-shape memory effect in response to light and pH sequentially.

20.
Br J Sports Med ; 50(15): 900-8, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26392595

ABSTRACT

BACKGROUND: There are many injection therapies for lateral epicondylalgia but there has been no previous comprehensive comparison, based on the Bayesian method. METHODS: The MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for appropriate literature. The outcome measurement was the pain score. Direct comparisons were performed using the pairwise meta-analysis, and network meta-analysis, based on a Bayesian model, was used to calculate the results of all of the potentially possible comparisons and rank probabilities. A sensitivity analysis was performed by excluding low-quality studies. The inconsistency of the model was assessed by means of the node-splitting method. Metaregression was used to assess the relationship between the sample size and the treatment effect. RESULTS: All of the injection treatments showed a trend towards better effects than placebo. Additionally, the peppering technique did not add additional benefits when combined with other treatments. No significant changes were observed by excluding low-quality studies in the sensitivity analysis. No significant inconsistencies were found according to the inconsistency analysis, and metaregression revealed that the sample size was not associated with the treatment effects. CONCLUSIONS: Some commonly used injection therapies can be considered treatment candidates for lateral epicondylalgia, such as botulinum toxin, platelet-rich plasma and autologous blood injection, but corticosteroid is not recommended. Hyaluronate injection and prolotherapy might be more effective, but their superiority must be confirmed by more research. The peppering technique is not helpful in injection therapies.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Arthralgia/drug therapy , Tennis Elbow/drug therapy , Adolescent , Adult , Aged , Bayes Theorem , Humans , Injections, Intra-Articular , Middle Aged , Randomized Controlled Trials as Topic , Watchful Waiting , Young Adult
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