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1.
Environ Sci Technol ; 54(3): 1929-1937, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31880146

RESUMO

The hydroxyl radical (•OH) scavenging capacity is a useful parameter for the design and operation of an advanced oxidation process (AOP) in water treatment. The scavenging capacity may change with time, and it would be useful to continuously measure this change to be able to optimize AOP doses. In this study, we first reviewed current methods for scavenging capacity measurement to identify strengths and weaknesses of each method. This information helped guide the design of an external calibration method to allow straightforward laboratory and field measurement of •OH scavenging capacity. The method used low-pressure UV/H2O2 as the •OH generation system, methylene blue (MB) as the probe compound, and isopropyl alcohol (IPA) as the standard. By monitoring, offline, the color decay of MB in a series of IPA solutions with different scavenging capacity, a calibration curve was established between the color decay rate and the scavenging capacity. The measured color decay in real water samples can then be used with this external calibration to estimate their scavenging capacity. Work was undertaken to ensure that the process would be robust under a wide range of water quality conditions. Parallel tests using this method compared with the benchmark methods confirmed its robustness and accuracy.


Assuntos
Radical Hidroxila , Purificação da Água , Calibragem , Peróxido de Hidrogênio , Oxirredução
2.
ORL J Otorhinolaryngol Relat Spec ; 81(5-6): 287-293, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31484181

RESUMO

OBJECTIVE: This study aims to assess the effectiveness of endoscopic tympanoplasty without mastoidectomy in the management of active mucosal chronic otitis media (COM) patients with mastoid and tympanic antrum lesions. METHODS: It is a prospective controlled study where 42 patients with active mucosal COM with mastoid and tympanic antrum lesions or normal aeration were recruited from the outpatient clinic of the otology department, Eye Ear Nose and Throat Hospital of Fudan University. All patients underwent endoscopic tympanoplasty without mastoidectomy by using the underlay technique with tragal cartilage graft with one side-perichondrium. The follow-up period was at least 3 months and results were evaluated in terms of graft uptake, ear dryness and hearing improvement. RESULTS: Statistics showed no significant difference in graft uptake between the mastoid and tympanic antrum lesions group (90.5%) and the normal aeration group (95.2%). There was no significant difference in ear dryness between the mastoid and tympanic antrum lesions group (95.2%) and the normal aeration group (100%). Hearing improvement was comparable in the 2 groups. CONCLUSION: Regardless of the occurrence of soft density shadows in temporal bone showed by high-resolution computerized tomography in the mastoid and tympanic antrum, mastoidectomy is an unnecessary procedure for dealing with active mucosal COM without cholesteatoma. Therefore, this study shows that endoscopic tympanoplasty without mastoidectomy may be applied to active mucosal COM without cholesteatoma.


Assuntos
Endoscopia/métodos , Mastoidectomia/métodos , Otite Média/cirurgia , Timpanoplastia/métodos , Adulto , Doença Crônica , Cartilagem da Orelha/transplante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Otite Média/diagnóstico por imagem , Estudos Prospectivos , Tomografia Computadorizada por Raios X
3.
Med Sci Monit ; 24: 5448-5456, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30078839

RESUMO

BACKGROUND Kanamycin and subsequent furosemide administration was applied to the healthy guinea pigs to induce deafness. MATERIAL AND METHODS Of the deafened guinea pigs, 10 were further infused with anti-infection procedures (Group B) and the other 10 animals did not undergo anti-infection procedures (Group C). In Group B, the deafened animals were able to restore cochlear and middle ear functions following the anti-infection procedure. In Group C, all animals developed cochlear and middle ear infections. RESULTS Compared to the healthy guinea pigs, hair cells and spiral ganglion neurons (SGN) of deafened animals (in Group B and Group C) were severely damaged. SGN density of deafened animals was significantly lower than that of healthy control animals in all ear turns except the basal turn. There was no significant difference between Group B and Group C in SGN density. The average optical density value of neurofilaments of deafened animals was also significantly decreased after the ototoxic drug administration. Notably, the density of the neurons in the cochlear nucleus region (CNR) of the brainstem were not significantly different between the healthy control guinea pigs and deafened animals. CONCLUSIONS Mimic cochlear implant surgery-induced cochlear infection caused no significant damage to the auditory pathway in ototoxic drug-induced deafened guinea pigs.


Assuntos
Vias Auditivas/fisiologia , Limiar Auditivo/efeitos dos fármacos , Implante Coclear/efeitos adversos , Animais , Vias Auditivas/microbiologia , Limiar Auditivo/fisiologia , Infecções Bacterianas , China , Cóclea/efeitos dos fármacos , Implante Coclear/métodos , Surdez/induzido quimicamente , Surdez/cirurgia , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Cobaias , Células Ciliadas Auditivas , Perda Auditiva Neurossensorial , Canamicina/farmacologia , Neurônios/efeitos dos fármacos , Otite/patologia , Gânglio Espiral da Cóclea/efeitos dos fármacos
5.
Environ Sci Technol ; 50(8): 4238-47, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27008571

RESUMO

This paper investigates the oxidation of oil sands process-affected water (OSPW) by potassium ferrate(VI). Due to the selectivity of ferrate(VI) oxidation, two-ring and three-ring fluorescing aromatics were preferentially removed at doses <100 mg/L Fe(VI), and one-ring aromatics were removed only at doses ≥100 mg/L Fe(VI). Ferrate(VI) oxidation achieved 64.0% and 78.4% removal of naphthenic acids (NAs) at the dose of 200 mg/L and 400 mg/L Fe(VI) respectively, and NAs with high carbon number and ring number were removed preferentially. (1)H nuclear magnetic resonance ((1)H NMR) spectra indicated that the oxidation of fluorescing aromatics resulted in the opening of some aromatic rings. Electron paramagnetic resonance (EPR) analysis detected signals of organic radical intermediates, indicating that one-electron transfer is one of the probable mechanisms in the oxidation of NAs. The inhibition effect of OSPW on Vibrio fischeri and the toxicity effect on goldfish primary kidney macrophages (PKMs) were both reduced after ferrate(VI) oxidation. The fluorescing aromatics in OSPW were proposed to be an important contributor to this acute toxicity. Degradation of model compounds with ferrate(VI) was also investigated and the results confirmed our findings in OSPW study.


Assuntos
Compostos de Ferro/química , Campos de Petróleo e Gás , Compostos de Potássio/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Aliivibrio fischeri/efeitos dos fármacos , Ácidos Carboxílicos/química , Ácidos Carboxílicos/isolamento & purificação , Espectroscopia de Ressonância de Spin Eletrônica , Concentração de Íons de Hidrogênio , Resíduos Industriais , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Oxirredução , Testes de Toxicidade/métodos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/toxicidade
6.
J Obstet Gynaecol Res ; 42(10): 1326-1335, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27307153

RESUMO

AIM: The aim of our study was to assess the levels of human epididymis protein 4 (HE4) with the common tumor marker carbohydrate antigen 125 (CA125) in the diagnosis and monitoring of therapy for primary fallopian tube carcinoma (PFTC). METHODS: Serum HE4 and CA125 levels from 82 PFTC patients and 154 patients with benign pelvic masses as the control were measured by Roche electrochemiluminescent immunoassay. HE4 determinations for surgery response and recurrence monitoring were assessed in PFTC patients. RESULTS: Serum HE4 and CA125 concentrations were significantly higher in PFTC patients compared with those seen in patients with benign pelvic masses (P < 0.001). Compared with CA125, HE4 had higher specificity, but lower sensitivity whether at early or advanced stage, and the combination of HE4 + CA125 led to higher sensitivity and specificity. HE4 + CA125 performed significantly better than CA125 or HE4 alone in early stage patients. In early stage the sensitivity was 35.7% for HE4 and 64.3% for CA125, while sensitivity for the combination of HE4 and CA125 could reach 71.4%. Furthermore, the two markers were associated with the progression and histology of PFTC. Serum HE4 level was closely correlated with surgical therapy. PFTC patients displayed a greater decline in the level of HE4 compared with CA125 (76.4% vs 55.7%). Combined with CA125, HE4 elevation better predicted recurrence in PFTC patients. CONCLUSIONS: This study indicated that serum HE4 levels are closely associated with PFTC and the outcome of surgical therapy and recurrence in Chinese patients.


Assuntos
Neoplasias das Tubas Uterinas/sangue , Neoplasias das Tubas Uterinas/diagnóstico , Proteínas/metabolismo , Adulto , Idoso , Antígeno Ca-125/sangue , Neoplasias das Tubas Uterinas/patologia , Neoplasias das Tubas Uterinas/cirurgia , Feminino , Humanos , Proteínas de Membrana/sangue , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Curva ROC , Resultado do Tratamento , Proteína 2 do Domínio Central WAP de Quatro Dissulfetos
7.
J Environ Manage ; 160: 254-62, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26119332

RESUMO

This study investigated the application of polyaluminum chloride (PACl) for the treatment of the oil sands process-affected water (OSPW). These coagulants are commonly used in water treatment with the most effective species reported to be Al13. PACl with 83.6% Al13 was synthesized using the slow base titration method and compared with a commercially available PACl in terms of aluminum species distribution, coagulation/flocculation (CF) performance, floc morphology, and contaminant removal. Both coagulants were effective in removing suspended solids, achieving over 96% turbidity removal at all applied coagulant doses (0.5-3.0 mM Al). The removal efficiencies of metals varied among different metals depending on their pKa values with metal cations having pKa values (Fe, Al, Ga, and Ti) below OSPW pH of 6.9-8.1 (dose dependent) being removed by more than 90%, while cations with higher pKa values (K, Na, Ca, Mg and Ni) had removals of less than 40%. Naphthenic acids were not removed due to their low molecular weights, negative charges, and hydrophilic characteristics at the OSPW pH. At the highest applied coagulant dose of 3.0 mM Al, the synthetic PACl reduced Vibrio fischeri inhibition effect to 43.3 ± 3.0% from 49.5 ± 0.4% in raw OSPW. In contrast, no reduction of toxicity was found for OSPW treated with the commercial PACl. Based on water quality and floc analyses, the dominant CF mechanism for particle removal during OSPW treatment was considered to be enmeshment in the precipitates (i.e., sweep flocculation). Overall, the CF using synthesized PACl can be a valuable pretreatment process for OSPW to create wastewater that is more easily treated by downstream processes.


Assuntos
Hidróxido de Alumínio/química , Campos de Petróleo e Gás , Purificação da Água/métodos , Floculação , Humanos , Resíduos Industriais , Metais Pesados/química , Qualidade da Água
8.
J Org Chem ; 79(9): 3908-16, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24702591

RESUMO

Efficient Rh(II)-catalyzed three-component reactions of 3-diazooxindoles and formaldehyde with either anilines or water were developed to give a series of substituted 3-amino-3-hydroxymethyloxindoles or 3-hydroxy-3-hydroxymethyloxindoles in good to excellent yields. In this atom- and step-economic transformation, Rh2(OAc)4-catalyzed decomposition of 3-diazooxindoles with anilines or water forms the corresponding active ammonium or oxonium ylides. Electrophilic trapping of the resulting ammonium ylides or oxonium ylides by formaldehyde in the form of formalin efficiently produces the title compounds in one step.


Assuntos
Compostos de Anilina/química , Formaldeído/química , Indóis/química , Compostos Organometálicos/química , Catálise , Indóis/síntese química , Estrutura Molecular , Oxindóis , Água/química
9.
ACS Omega ; 9(21): 23013-23020, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38826532

RESUMO

A fluorosulfate ion (FSO3-) is a hydrolysis product of sulfuryl fluoride (SO2F2), which is widely used to fumigate buildings, soil, construction materials, and postharvest commodities, and is a potent greenhouse gas. It is a potential marker for biological exposure to SO2F2 and for monitoring the progress of reactions used to scrub SO2F2 from fumigation vent gases. Here, we report a simple and inexpensive potentiometric method for determining FSO3- using a commercial nitrate-selective electrode and discuss its application. The method is suitable for solutions between 0.0025 mM and 660 mM FSO3- at initial pH between 5 and 9. Halide interference depends on its molar ratio to FSO3- and follows the sequence, F- < Cl- < Br- ≪ I-. Halide interference can be eliminated by adding silver sulfate. Interference by bicarbonate can be eliminated by H2SO4 pretreatment, and interference by phosphate or pyrophosphate by MgSO4 addition. Sulfate does not interfere, as it does in ion chromatography. Satisfactory method detection limits for FSO3- in spiked aqueous extracts of 11 fruits were obtained. The method accurately quantified the yield of FSO3- relative to that of F- in base hydrolysis of SO2F2. This study demonstrates that the developed method is highly selective, convenient, and sensitive and thus can be of great value in practice.

10.
Water Res ; 261: 122068, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39003879

RESUMO

Electrochemical advanced oxidation processes (EAOPs) have shown great promise for treating industrial wastewater contaminated with phenolic compounds. However, the presence of chloride in the wastewater leads to the production of undesirable chlorinated organic and inorganic byproducts, limiting the application of EAOPs. To address this challenge, we investigated the potential of incorporating Fe(II) and Fe(III) into the EAOPs with a boron-doped diamond (BDD) anode under near-neutral conditions. Our findings revealed that both Fe(II) and Fe(III) facilitated the generation of high-valent iron-oxo species (Fe(IV) and Fe(V)) in the anodic compartment, thereby reducing the oxidation contribution of reactive chlorine species. Remarkably, the addition of 1000 µM Fe(II) under high chloride conditions resulted in over a 2.8-fold increase in the oxidation rate of 50 µM phenolic contaminants at pH 6.5. Furthermore, 1000 µM Fe(II) contributed to a reduction of more than 66% in the formation of chlorinated byproducts, consequently enhancing the biodegradability of the treated water. Additionally, transitioning from batch mode to continuous flow mode further amplified the positive effects of Fe(II) on the EAOPs. Overall, this study presents a modified electrochemical approach that simultaneously enhanced the degradation of phenolic contaminants and improved the biodegradability of wastewater with high chloride concentrations.


Assuntos
Cloretos , Técnicas Eletroquímicas , Ferro , Oxirredução , Fenóis , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Fenóis/química , Cloretos/química , Ferro/química , Poluentes Químicos da Água/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Eletrodos , Boro/química
11.
Sci Rep ; 14(1): 14212, 2024 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902448

RESUMO

Humans can easily perform various types of hugs in human contact and affection experience. With the prevalence of robots in social applications, they would be expected to possess the capability of hugs as humans do. However, it is still not an easy task for robots, considering the complex force and spatial constraints of robot hugs. In this work, we propose the HUG taxonomy, which distinguishes between different hugging patterns based on human demonstrations and prior knowledge. In this taxonomy, hugs are arranged according to (1) hugging tightness, (2) hugging style, and (3) bilateral coordination, resulting in 16 different hug types. We then further study the hug type preference of humans in different scenarios and roles. Furthermore, we propose a rule-based classification system to validate the potential of this taxonomy in human-robot hugs based on a humanoid robot with an E-skin of contact sensation. The HUG taxonomy could provide human hugging behavior information in advance, facilitating the action control of humanoid robots. We believe the results of our work can benefit future studies on human-robot hugging interactions.


Assuntos
Robótica , Humanos , Robótica/métodos
12.
Nat Commun ; 15(1): 128, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167856

RESUMO

The demand for milk has increased globally, accompanied by an increase in waste milk. Here, we provide an artificial humification technology to recycle waste milk into an agricultural nano-fertilizer. We use KOH-activated persulfate to convert waste milk into fulvic-like acid and humic-like acid. We mix the product with attapulgite to obtain a slow-release nano fulvic-like acid fertilizer. We apply this nano-fertilizer to chickweeds growing in pots, resulting in improved yield and root elongation. These results indicate that waste milk could be recycled for agricultural purposes, however, this nano-fertilizer needs to be tested further in field experiments.


Assuntos
Fertilizantes , Resíduos , Animais , Fertilizantes/análise , Leite/química , Agricultura/métodos , Solo
13.
Heliyon ; 9(10): e20988, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916124

RESUMO

Due to the frequent occurrence of piracy incidents, normal trade, and transportation activities have been hindered. This paper uses the Piracy and Armed Robbery dataset in the Global Integrated Shipping Information System to analyze the types and evolutionary characteristics of shipping risk caused by piracy and the piracy behavior patterns in different seas. This study found that there are three regions with high incidence of piracy in the world, and their gathering centers change dynamically over time. Piracy incidents can be divided into four categories based on the quantitative assessment of shipping risk caused by piracy. Shipping risk caused by piracy shows different evolution characteristics in different seas, affected by factors such as the evolution of national political situations and anti-piracy measures. Based on the qualitative assessment of the shipping risk caused by piracy, the piracy corpus reflects the diverse patterns of piracy in different seas. In the process of pirate attacks, the diversity is mainly manifested in violence and selectivity. In the consequences of pirate attacks, the targets that pirates pay attention to vary significantly in different seas. This research will help to strengthen the dynamic monitoring of shipping risk caused by piracy, and further contribute to the research on maritime transport safety.

14.
Water Res ; 242: 120227, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37354844

RESUMO

UV/Cl and UV/H2O2 are advanced oxidation processes (AOPs) used for drinking water treatment and water reuse. This work explored the hypothesis that UV/Cl becomes more competitive to UV/H2O2 at neutral-to-high pH as the concentration of total organic carbon (TOC) increases. Lab experiments and kinetic modelling were used to compare initial pseudo first-order contaminant decay rate coefficients between the AOPs at various pH and TOC conditions. The relative effect of increasing TOC concentrations on UV/Cl vs. UV/H2O2 depended on the pH, contaminant, and organic matter reactivity towards radicals. For example, while the reaction rate coefficients during both AOPs generally decreased with increasing TOC, the UV/Cl reaction rate coefficients for the solely •OH-reactive sucralose decreased 41-138% less than the UV/H2O2 coefficients as the TOC concentration was increased from 0 to 5 mg-C L-1. However, UV/Cl was more affected than UV/H2O2 when targeting caffeine (a contaminant reactive to chlorine radicals). The data were used to define TOC-pH conditions for which either AOP would be more energy-efficient, under a set of standard conditions. The results suggest that UV/Cl may be competitive to UV/H2O2 under a wider range of treatment scenarios than has been conventionally thought based on tests in pure water.

15.
Water Res ; 243: 120361, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37487357

RESUMO

Peracetic acid (PAA) may be used in drinking water treatment for pre-oxidation and mussel control at the intake. PAA may exert a downstream chlorine demand, but full details of this reaction have not been reported. There are three possible mechanisms of this demand: (1) PAA may react directly with chlorine; (2) PAA exists in equilibrium with hydrogen peroxide, which is known to react with chlorine; and (3) as H2O2 reacts with chlorine, PAA will hydrolyze to form more H2O2 to re-establish PAA/H2O2 equilibrium, thereby serving as an indirect reservoir of chlorine demand. While the H2O2 reaction with chlorine is well known, the other mechanisms of possible PAA-induced chlorine demand have not previously been investigated. The observed molar stoichiometric ratio of PAA to free chlorine (n) for the presumed direct PAA + free chlorine reaction was determined to be approximately 2, and the corresponding observed reaction rate coefficients at pH 6, 7, 8, and 9 were 2.76, 3.14, 1.61, 10.1 M-n·s-1, respectively (at 25 °C). With these estimated values, a kinetic model was built to predict the chlorine demand by PAA. The results suggest that chlorine demand from PAA is likely to be negligible over the course of several days (e.g., < 20% chlorine loss) for most conditions except for high pH (e.g., >8) and high PAA:Cl2 molar ratios (e.g., >2:1).


Assuntos
Água Potável , Poluentes Químicos da Água , Ácido Peracético/análise , Cloro , Peróxido de Hidrogênio , Desinfecção/métodos , Cloretos
16.
J Hazard Mater ; 458: 131909, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37459759

RESUMO

Interaction of antibiotics with metal ions in aquatic environments, commonly occurring to form complexes, may affect the migration, transformation and reactivity of residual antibiotics. This study demonstrates the photolysis of Fe(III) by UV irradiation at pH 3.5, as an advanced oxidation process, to produce •OH for the abatement of a common broad-spectrum antibiotic compound, tetracycline (TET). The dimethylamino (-N(CH3)2) and hydroxyl (-OH) groups of TET were determined as the binding sites for the complexation with Fe(III) via a series of novel characterization approaches. The complexation stoichiometry of Fe(III)-TET complexation, including the complexation ratio, constants and percentages, was determined via a complexometric titration based on the UV differential spectroscopy. The complexation constant was determined to be 21,240 ± 1745 L·mol-1 under the designed conditions. Complexation of TET with Fe(III) enhanced its degradation in the UV/Fe(III) process, through the promotion of the •OH generation by inhibiting hydrolysis-precipitation process of Fe(III) and enhancing Fe(III)/Fe(II) cycle and the acceleration of mass transfer between •OH and TET. This finding provides new insights into the role of complexation in the fate of residual antibiotics in the UV/Fe(III) process. The reduced overall ecotoxicity during the TET abatement, evaluated by the toxicity variation through ECOSAR program, provides the UV/Fe(III) process with a theoretical feasibility for water decontamination in actual applications.


Assuntos
Antibacterianos , Poluentes Químicos da Água , Antibacterianos/química , Compostos Férricos/química , Fotólise , Tetraciclina , Raios Ultravioleta , Poluentes Químicos da Água/química , Oxirredução
17.
Materials (Basel) ; 16(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37569972

RESUMO

To reduce the structural deterioration of mass concrete structures from temperature cracks, and lower energy consumption caused by the traditional mass concrete hydration heat cooling process, this paper reports the preparation of concrete temperature-controlled phase change aggregate (PCA) by a vacuum compaction method using light and high-strength black ceramite and No. 58 fully refined paraffin wax as phase change material (PCM), and the encapsulation technology of the aggregate by using superfine cement and epoxy resin. Further, through laboratory tests, the cylinder compressive strength, thermal stability and mixing breakage rate of the encapsulated PCA were tested, and the differences in mechanical properties such as compressive strength, flexural strength and splitting tensile strength between phase change aggregate concrete (PCAC) and ordinary concrete were studied. A test method was designed to test the heat storage effect of PCA, and the temperature control effect of PCAC was analyzed based on the law of conservation of energy. The research conclusions are as follows: (1) Both superfine cement and epoxy resin shells increase the strength of the aggregate, with the epoxy resin increasing it more than the superfine cement. The thermal stabilization of the PCA is good after encapsulation of superfine cement and epoxy resin. However, PCA encapsulated in superfine cement is more easily crushed than that encapsulated in epoxy resin. (2) Under the condition of water bath heating and semi-insulation, when the water bath temperature reaches 85 °C, the temperature difference between the PCA and the common stone aggregate can be up to 6 °C. Based on the law of energy conservation, the test results will be converted to mass concrete with the same volume of aggregate mixture;, the difference of PCAC and ordinary concrete temperature can be up to 10 °C, so the temperature control effect is significant. (3) The mechanical properties of PCAC with 100% aggregate replacement rate compared to ordinary concrete are reduced to varying degrees, and the performance decline of the epoxy-encapsulated PCA is smaller than that encapsulated with superfine cement; in an actual project, it is possible to improve the concrete grade to make up for this defect.

18.
Curr Eye Res ; 48(1): 51-59, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36264060

RESUMO

PURPOSE: The purpose of this study was to use the neural network to distinguish optic edema (ODE), and optic atrophy from normal fundus images and try to use visualization to explain the artificial intelligence methods. METHODS: Three hundred and sixty-seven images of ODE, 206 images of optic atrophy, and 231 images of normal fundus were used, which were provided by two hospitals. A set of image preprocessing and data enhancement methods were created and a variety of different neural network models, such as VGG16, VGG19, Inception V3, and 50-layer Deep Residual Learning (ResNet50) were used. The accuracy, recall, F1-score, and ROC curve under different networks were analyzed to evaluate the performance of models. Besides, CAM (class activation mapping) was utilized to find the focus of neural network and visualization of neural network with feature fusion. RESULTS: Our image preprocessing and data enhancement method significantly improved the accuracy of model performance by about 10%. Among the networks, VGG16 had the best effect, as the accuracy of ODE, optic atrophy and normal fundus were 98, 90, and 95%, respectively. The macro-average and micro-average of VGG16 both reached 0.98. From CAM we can clearly find out that the focus area of the network is near the optic cup. From feature fusion images, we can find out the difference between the three types fundus images. CONCLUSION: Through image preprocessing, data enhancement, and neural network training, we applied artificial intelligence to identify ophthalmic diseases, acquired the focus area through CAM, and identified the difference between the three ophthalmic diseases through neural network middle layers visualization. With the help of assistant diagnosis, ophthalmologists can evaluate cases more precisely and more clearly.


Assuntos
Aprendizado Profundo , Atrofia Óptica , Doenças do Nervo Óptico , Humanos , Inteligência Artificial , Fundo de Olho , Doenças do Nervo Óptico/diagnóstico
19.
Adv Sci (Weinh) ; 10(12): e2205744, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36808712

RESUMO

Nerve guidance conduits (NGCs) have become a promising alternative for peripheral nerve regeneration; however, the outcome of nerve regeneration and functional recovery is greatly affected by the physical, chemical, and electrical properties of NGCs. In this study, a conductive multiscale filled NGC (MF-NGC) consisting of electrospun poly(lactide-co-caprolactone) (PCL)/collagen nanofibers as the sheath, reduced graphene oxide /PCL microfibers as the backbone, and PCL microfibers as the internal structure for peripheral nerve regeneration is developed. The printed MF-NGCs presented good permeability, mechanical stability, and electrical conductivity, which further promoted the elongation and growth of Schwann cells and neurite outgrowth of PC12 neuronal cells. Animal studies using a rat sciatic nerve injury model reveal that the MF-NGCs promote neovascularization and M2 transition through the rapid recruitment of vascular cells and macrophages. Histological and functional assessments of the regenerated nerves confirm that the conductive MF-NGCs significantly enhance peripheral nerve regeneration, as indicated by improved axon myelination, muscle weight increase, and sciatic nerve function index. This study demonstrates the feasibility of using 3D-printed conductive MF-NGCs with hierarchically oriented fibers as functional conduits that can significantly enhance peripheral nerve regeneration.


Assuntos
Regeneração Nervosa , Impressão Tridimensional , Nervo Isquiático , Técnicas Eletroquímicas , Neuritos , Animais , Ratos , Linhagem Celular
20.
Int J Bioprint ; 8(2): 543, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669322

RESUMO

Intimal hyperplasia and restenosis caused by excessive proliferation of smooth muscle cells (SMC) are the main factors for the failure of stent implantation. Drug-eluting stents carried with antiproliferative drugs have emerged as a successful approach to alleviate early neointimal development. However, these agents have been reported to have an undesirable effect on re-endothelialization. In this study, we proposed an integrated bioresorbable stent coated with dipyridamole (DP)-loaded poly(D,L-lactide) (PDLLA) nanofibers. Three-dimensional (3D) bioresorbable stents were fabricated by printing on a rotation mandrel using polycaprolactone (PCL), and the stents were further coated with PDLLA/DP nanofibers. The in vitro degradation and drug release evaluation illustrated the potential for long-term release of DP. Stents coated with PDLLA/DP nanofibers showed excellent hemocompatibility. The cell viability, proliferation, and morphology analysis results revealed that stents coated with PDLLA/DP nanofibers could prevent the proliferation of SMC and have no adverse effects on endothelial cells. The in vivo implantation of stents coated with PDLLA/DP nanofibers showed initial patency and continuous endothelialization and alleviated neointimal formation. The attractive in vitro and in vivo performance indicated its potential for restenosis prevention and endothelialization.

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