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1.
Theranostics ; 11(19): 9415-9430, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646378

RESUMO

The feasibility of personalized medicine for cancer treatment is largely hampered by costly, labor-intensive and time-consuming models for drug discovery. Herein, establishing new pre-clinical models to tackle these issues for personalized medicine is urgently demanded. Methods: We established a three-dimensional tumor slice culture (3D-TSC) platform incorporating label-free techniques for time-course experiments to predict anti-cancer drug efficacy and validated the 3D-TSC model by multiphoton fluorescence microscopy, RNA sequence analysis, histochemical and histological analysis. Results: Using time-lapse imaging of the apoptotic reporter sensor C3 (C3), we performed cell-based high-throughput drug screening and shortlisted high-efficacy drugs to screen murine and human 3D-TSCs, which validate effective candidates within 7 days of surgery. Histological and RNA sequence analyses demonstrated that 3D-TSCs accurately preserved immune components of the original tumor, which enables the successful achievement of immune checkpoint blockade assays with antibodies against PD-1 and/or PD-L1. Label-free multiphoton fluorescence imaging revealed that 3D-TSCs exhibit lipofuscin autofluorescence features in the time-course monitoring of drug response and efficacy. Conclusion: This technology accelerates precision anti-cancer therapy by providing a cheap, fast, and easy platform for anti-cancer drug discovery.

2.
J Digit Imaging ; 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34519954

RESUMO

We developed a deep learning-based super-resolution model for prostate MRI. 2D T2-weighted turbo spin echo (T2w-TSE) images are the core anatomical sequences in a multiparametric MRI (mpMRI) protocol. These images have coarse through-plane resolution, are non-isotropic, and have long acquisition times (approximately 10-15 min). The model we developed aims to preserve high-frequency details that are normally lost after 3D reconstruction. We propose a novel framework for generating isotropic volumes using generative adversarial networks (GAN) from anisotropic 2D T2w-TSE and single-shot fast spin echo (ssFSE) images. The CycleGAN model used in this study allows the unpaired dataset mapping to reconstruct super-resolution (SR) volumes. Fivefold cross-validation was performed. The improvements from patch-to-volume reconstruction (PVR) to SR are 80.17%, 63.77%, and 186% for perceptual index (PI), RMSE, and SSIM, respectively; the improvements from slice-to-volume reconstruction (SVR) to SR are 72.41%, 17.44%, and 7.5% for PI, RMSE, and SSIM, respectively. Five ssFSE cases were used to test for generalizability; the perceptual quality of SR images surpasses the in-plane ssFSE images by 37.5%, with 3.26% improvement in SSIM and a higher RMSE by 7.92%. SR images were quantitatively assessed with radiologist Likert scores. Our isotropic SR volumes are able to reproduce high-frequency detail, maintaining comparable image quality to in-plane TSE images in all planes without sacrificing perceptual accuracy. The SR reconstruction networks were also successfully applied to the ssFSE images, demonstrating that high-quality isotropic volume achieved from ultra-fast acquisition is feasible.

3.
Acta Virol ; 65(3): 273-278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34565155

RESUMO

African swine fever (ASF) is an acute and severe infectious disease that seriously endangers the global porcine industry. In order to develop ASF serodiagnostic reagents with high specificity and sensitivity, in the present study, the antigenic epitopes of P72 protein of African swine fever virus (ASFV) were analyzed, and the ASFV multi-epitope fusion gene MeP72 in tandem with the dominant linear epitopes was constructed. The recombinant multi-epitope fusion MeP72 (reMeP72) was prepared in Escherichia coli. A colloidal gold-based immunochromatographic assay (CGIA) based on reMeP72 was developed for the detection of antibodies against ASFV. A total of 139 pig clinical serum samples were used for assessment of the potential diagnostic value of reMeP72. The results showed that CGIA did not cross-react with positive sera of viruses, such as classical swine fever virus (CSFV), porcine circovirus type 2 (PCV2), pseudorabies virus (PRV), porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza virus (SIV), showing high specificity. Sensitivity analysis showed that CGIA could detect ASFV-positive serum at a dilution of 1:64. Compared with commercial ASFV kits, the sensitivity and specificity of ASFV CGIA based on reMeP72 protein were 85.7% and 97.6%, respectively. The agreement rate of the two methods was 96.4%, showing a good detection performance. The results indicated that the reMeP72 was of potential value for the serodiagnosis of ASF. Keywords: African swine fever virus; P72 gene; antigenic protein; colloidal gold-based immunochromatographic assay.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vírus da Síndrome Respiratória e Reprodutiva Suína , Febre Suína Africana/diagnóstico , Vírus da Febre Suína Africana/genética , Animais , Epitopos , Testes Sorológicos , Suínos
4.
J Orthop Surg Res ; 16(1): 577, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34587970

RESUMO

BACKGROUND: This study aimed to share our experience of anterior ring fixation failure for unstable pelvic fractures and propose corresponding treatment strategies. MATERIALS: From January 2009 to December 2018, 93 charts of patients with pelvic fractures were retrospectively reviewed. Patients with failure of the anterior ring internal fixation within 3 months after initial surgery were analyzed. Quality of reduction was evaluated using the Majeed scoring system. Patients aging ≥ 18 years, with unstable pelvic fractures, Tile classification type B and type C pelvic fractures, combined injury of other organs that did not affect the operation and without important neurovascular damage were included. The exclusion criteria included: (1) pathological fracture, or combined with pelvic bone tumor or severe osteoporosis; (2) femoral fracture and thoracolumbar fracture; (3) open pelvic fracture; (4) Morel-Lavallée injury; (5) complicated acetabular fracture. The quality of the reduction of the anterior pelvic ring injury was evaluated on the x-ray film using the Majeed scoring system. RESULTS: According to the Tile classification of fracture, there were 23 cases of type B1, 17 cases of type B2, 11 cases of type B3, 28 cases of type C1, 6 cases of type C2, and 8 cases of type C3. The duration from injury to pelvic internal fixation ranged from 5 to 28 days. Seven out of 93 patients experienced failure of internal fixation of the anterior pelvic ring within 3 months, including 2 patients fixed with an external fixator and 5 patients fixed with a plate. Five patients undergoing revision surgery were followed up for 6-36 months with an average of 18 months. According to Majeed's score at the last follow-up in the 5 patients undergoing revision surgery, there were 2 cases of excellent, 2 cases of good, 1 case of fair. The excellent and good rate reached 80%. CONCLUSION: The treatment of complicated unstable pelvic fractures requires performing internal fixation surgery within 2 weeks. It is necessary to make a preoperative plan and stabilize the posterior ring first, avoiding a single steel plate crossing the pubic symphysis.

5.
Int J Biol Macromol ; 191: 230-242, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34536474

RESUMO

G-quadruplexes have become attractive drug targets in cancer therapy. However, due to the polymorphism of G-quadruplex structures, it is difficult to experimentally verify the relevant structures of multiple intermediates and transition states in dynamic equilibrium. Hence, understanding the mechanism by which structural conversions of G-quadruplexes occur is still challenging. We conducted targeted molecular dynamics simulation with umbrella sampling to investigate how salt affects the conformational conversion of human telomeric G-quadruplex. Our results explore a unique view into the structures and energy barrier of the intermediates and transition states in the interconversion process. The pathway of G-quadruplex conformational interconversion was mapped out by a free energy landscape, consisting of branched parallel pathways with multiple energy basins. We propose a salt-controlled mechanism that as the salt concentration increases, the conformational conversion mechanism switches from multi-pathway folding to sequential folding pathways. The hybrid-I and hybrid-II structures are intermediates in the basket-propeller transformation. In high-salt solutions, the conformational conversion upon K+ binding is more feasible than upon Na+ binding. The free energy barrier for conformational conversions ranges from 1.6 to 4.6 kcal/mol. Our work will be beneficial in developing anticancer agents.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34469098

RESUMO

There has been a surge of interest in applying deep learning (DL) to microstructure generation and materials design. However, existing DL-based methods are generally limited in generating (1) microstructures with high resolution, (2) microstructures with high variability, (3) microstructures with guaranteed periodicity, and (4) highly controllable microstructures. In this study, a DL approach based on a stacked generative adversarial network (StackGAN-v2) is proposed to overcome these shortcomings. The presented modeling approach can reconstruct high-fidelity microstructures of additively manufactured piezoceramics with different resolutions, which are statistically equivalent to original microstructures either experimentally observed or numerically predicted. Advantages of the proposed modeling approach are also illustrated in terms of its capability in controlling the probability density function (PDF) of grain size, grain orientation, and micropore in a large space, which would have significant benefits in exploring the effects of these microstructure features on the piezoelectricity of piezoceramics. In the meantime, periodicity of the microstructures has been successfully introduced in the developed model, which can critically reduce the simulation volume to be considered as a representative volume element (RVE) during computational calculation of piezoelectric properties. Therefore, this DL approach can significantly accelerate the process of designing optimal microstructures when integrating with computational methods (e.g., fast Fourier spectral iterative perturbation (FSIPM)) to achieve desired piezoelectric properties. The proposed DL-based method is generally applicable to optimal design of a variety of periodic microstructures, allowing for maximum explorations of design spaces and fine manipulations of microstructural features.

7.
J Formos Med Assoc ; 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34446339

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a common cause of childhood pneumonia, but there is limited understanding of whether bacterial co-infections affect clinical severity. METHODS: We conducted a retrospective cohort study at National Taiwan University Hospital from 2010 to 2019 to compare clinical characteristics and outcomes between RSV with and without bacterial co-infection in children without underlying diseases, including length of hospital stay, intensive care unit (ICU) admission, ventilator use, and death. RESULTS: Among 620 inpatients with RSV pneumonia, the median age was 1.33 months (interquartile range, 0.67-2 years); 239 (38.6%) under 1 year old; 366 (59.0%) males; 201 (32.4%) co-infected with bacteria. The three most common bacteria are Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae. The annually seasonal analysis showed that spring and autumn were peak seasons, and September was the peak month. Compared with single RSV infection, children with bacterial co-infection were younger (p = 0.021), had longer hospital stay (p < 0.001), needed more ICU care (p = 0.02), had higher levels of C-reactive protein (p = 0.009) and more frequent hyponatremia (p = 0.013). Overall, younger age, bacterial co-infection (especially S. aureus), thrombocytosis, and lower hemoglobin level were associated with the risk of requiring ICU care. CONCLUSION: RSV related bacterial co-infections were not uncommon and assoicated with ICU admission, especially for young children, and more attention should be given. For empirical antibacterial treatment, high-dose amoxicillin-clavulanic acid or ampicillin-sulbactam was recommended for non-severe cases; vancomycin and third-generation cephalosporins were suggested for critically ill patients requiring ICU care.

8.
J Formos Med Assoc ; 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34454794

RESUMO

BACKGROUND: Recurrent pneumonia is uncommon in children and few studies investigate the clinical impact of underlying diseases on this issue. This study aimed to explore the difference in clinical manifestations, pathogens, and prognosis of recurrent pneumonia in children with or without underlying diseases. METHODS: We conducted a retrospective study of pediatric recurrent pneumonia from 2007 to 2019 in National Taiwan University Hospital. Patients under the age of 18 who had two or more episodes of pneumonia in a year were included, and the minimum interval of two pneumonia episodes was more than one month. Aspiration pneumonia was excluded. Demographic and clinical characteristics of patients were collected and compared. RESULTS: Among 8508 children with pneumonia, 802 (9.4%) of them had recurrent pneumonia. Among these 802 patients, 655 (81.7%) had underlying diseases including neurological disorders (N = 252, 38.5%), allergy (N = 211, 32.2%), and cardiovascular diseases (N = 193, 29.5%). Children without underlying diseases had more viral bronchopneumonia (p < 0.001). Children with underlying diseases were more likely to acquire Staphylococcus aureus (p = 0.001), and gram-negative bacteriae, more pneumonia episodes (3 vs 2, p < 0.001), a longer hospital stay (median: 7 vs. 4 days, p < 0.001), a higher ICU rate (28.8% vs 3.59%, p < 0.001), and a higher case-fatality rate (5.19% vs 0%, p < 0.001) than those without underlying diseases. CONCLUSION: Children with underlying diseases, prone to have recurrent pneumonia and more susceptible to resistant microorganisms, had more severe diseases and poorer clinical outcomes. Therefore, more attention may be paid on clinical severity and the therapeutic plan.

9.
Plant Biotechnol J ; 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388296

RESUMO

Soybean is one of the most important oilseed and fodder crops. Benefiting from the efforts of soybean breeders and the development of breeding technology, large number of germplasm has been generated over the last 100 years. Nevertheless, soybean breeding needs to be accelerated to meet the needs of a growing world population, to promote sustainable agriculture and to address future environmental changes. The acceleration is highly reliant on the discoveries in gene functional studies. The release of the reference soybean genome in 2010 has significantly facilitated the advance in soybean functional genomics. Here, we review the research progress in soybean omics (genomics, transcriptomics, epigenomics and proteomics), germplasm development (germplasm resources and databases), gene discovery (genes that are responsible for important soybean traits including yield, flowering and maturity, seed quality, stress resistance, nodulation and domestication) and transformation technology during the past decade. At the end, we also briefly discuss current challenges and future directions.

10.
J Vis Exp ; (173)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34338666

RESUMO

Instead of using genetic methods like RNA interference (RNAi) and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated endonuclease Cas9, a physical barrier was microsurgically inserted between the testes of Spodoptera litura to study the impact of this microsurgery on its growth and reproduction. After inserting aluminum foil between the testes, insect molting during metamorphosis proceeded normally. Insect growth and development were not remarkably altered; however, the number of sperm bundles changed if testes fusion was stopped by the microsurgery. These findings imply that blocking testicular fusion can influence male reproduction capability. The method can be further applied to interrupt communication between organs to study the function of specific signaling pathways. Compared to conventional surgery, microsurgery only requires freezing anesthetization, which is preferable to carbon dioxide anesthetization. Microsurgery also minimizes the surgery site area and facilitates wound healing. However, the selection of materials with specific functions needs further investigation. Avoiding tissue injury is crucial when making incisions during the operation.

11.
Transl Vis Sci Technol ; 10(9): 18, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34403475

RESUMO

Purpose: Fundus images are typically used as the sole training input for automated diabetic retinopathy (DR) classification. In this study, we considered several well-known DR risk factors and attempted to improve the accuracy of DR screening. Metphods: Fusing nonimage data (e.g., age, gender, smoking status, International Classification of Disease code, and laboratory tests) with data from fundus images can enable an end-to-end deep learning architecture for DR screening. We propose a neural network that simultaneously trains heterogeneous data and increases the performance of DR classification in terms of sensitivity and specificity. In the current retrospective study, 13,410 fundus images and their corresponding nonimage data were collected from the Chung Shan Medical University Hospital in Taiwan. The images were classified as either nonreferable or referable for DR by a panel of ophthalmologists. Cross-validation was used for the training models and to evaluate the classification performance. Results: The proposed fusion model achieved 97.96% area under the curve with 96.84% sensitivity and 89.44% specificity for determining referable DR from multimodal data, and significantly outperformed the models that used image or nonimage information separately. Conclusions: The fusion model with heterogeneous data has the potential to improve referable DR screening performance for earlier referral decisions. Translational Relevance: Artificial intelligence fused with heterogeneous data from electronic health records could provide earlier referral decisions from DR screening.


Assuntos
Aprendizado Profundo , Diabetes Mellitus , Retinopatia Diabética , Inteligência Artificial , Retinopatia Diabética/diagnóstico , Humanos , Encaminhamento e Consulta , Estudos Retrospectivos
12.
J Formos Med Assoc ; 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34332830

RESUMO

BACKGROUND/PURPOSE: Influenza is frequently complicated with bacterial co-infection. This study aimed to disclose the significance of Streptococcus pneumoniae co-infection in children with influenza. METHODS: We retrospectively reviewed medical records of pediatric patients hospitalized for influenza with or without pneumococcal co-infection at the National Taiwan University Hospital from 2007 to 2019. Clinical characteristics and outcomes were compared between patients with and without S. pneumoniae co-infection. RESULTS: There were 558 children hospitalized for influenza: 494 had influenza alone whereas 64 had S. pneumoniae co-infection. Patients with S. pneumoniae co-infection had older ages, lower SpO2, higher C-Reactive Protein (CRP), lower serum sodium, lower platelet counts, more chest radiograph findings of patch and consolidation on admission, longer hospitalization, more intensive care, longer intensive care unit (ICU) stay, more mechanical ventilation, more inotropes/vasopressors use, more surgical interventions including video-assisted thoracoscopic surgery (VATS) and extracorporeal membrane oxygenation (ECMO), and higher case-fatality rate. CONCLUSION: Compared to influenza alone, patients with S. pneumoniae co-infection had more morbidities and mortalities. Pneumococcal co-infection is considered when influenza patients have lower SpO2, lower platelet counts, higher CRP, lower serum sodium, and more radiographic patches and consolidations on admission.

13.
Sensors (Basel) ; 21(12)2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34208262

RESUMO

It is important for equipment to operate safely and reliably so that the working state of mechanical parts pushes forward an immense influence. Therefore, in order to enhance the dependability and security of mechanical equipment, to accurately predict the changing trend of mechanical components in advance plays a significant role. This paper introduces a novel condition prediction method, named error fusion of hybrid neural networks (EFHNN), by combining the error fusion of multiple sparse auto-encoders with convolutional neural networks for predicting the mechanical condition. First, to improve prediction accuracy, we can use the error fusion of multiple sparse auto-encoders to collect multi-feature information, and obtain a trend curve representing machine condition as well as a threshold line that can indicate the beginning of mechanical failure by computing the square prediction error (SPE). Then, convolutional neural networks predict the state of the machine according to the original data when the SPE value exceeds the threshold line. It can be seen from this result that the EFHNN method in the prediction of mechanical fault time series is available and superior.


Assuntos
Redes Neurais de Computação
14.
Langmuir ; 37(29): 8776-8788, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34266237

RESUMO

With the purpose of oil energy recovery as well as achieving efficiency of oil/water separation, hydrophobic mesh materials have attracted extensive attention. However, fabrication of the current methods is not environmentally friendly, has high energy consumption, and creates serious pollution. Inspired by lotus leaves and rose petals, a biomimetic superhydrophobic surface was fabricated prepared on a stainless steel mesh by an in situ chemical reduction method with simple operation and mild conditions. The results of SEM, XRD, and XPS demonstrated that the mesh shows a stable and uniform moss-like rough structured surface. The SSM/Ag/ODA mesh, which was modified by moss-like Ag nanoclusters and low surface energy agents, has excellent superhydrophobicity with an excellent oil/water separation efficiency that reached up to 99.8%. The silver mirror phenomenon formed by the Ag nanoclusters further confirmed that silver ions were reduced and attached to the surface of the mesh. Moreover, the mesh can maintain superhydrophobicity under harsh conditions, such as a high concentration of a salty solution, organic solvents, alkaline, acidic solution, and even long-time UV irradiation, etc. More importantly, the modified mesh has excellent physical stability, in which the water contact angle on the mesh can be maintained above 150° after harsh mechanical wear. The hydrophobic mesh showed great potential to be applied for highly efficient oil/water separation and oil energy recovery even under complex and harsh conditions.


Assuntos
Óleos , Prata , Biomimética , Interações Hidrofóbicas e Hidrofílicas , Telas Cirúrgicas
15.
Analyst ; 146(15): 4775-4780, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34231558

RESUMO

Cholesterol is an essential compound for human health, and a high or low concentration of cholesterol is closely related to various diseases. Thus, developing a simple method for POCT of cholesterol has great significance in clinical diagnosis. In this work, alginate (Alg) hydrogels with glow-type chemiluminescence (CL) were prepared and applied for rapid and quantitative cholesterol detection via a smartphone. The glow-type CL hydrogels (HRP/COD/luminol/Alg hydrogels) contained luminol as a chemiluminescent reagent, horseradish peroxidase (HRP) and cholesterol oxidase (COD) for enzymatic cascade reactions. The HRP/COD/luminol/Alg hydrogels exhibited outstanding stability, which effectively avoided the enzyme inactivation during long-term storage. Furthermore, the HRP/COD/luminol/Alg hydrogels exhibited longer and more stable glow-type CL. With the help of COD catalytic specificity for cholesterol and bi-enzymatic cascade reactions, the glow-type CL hydrogels realized the specific and sensitive detection of cholesterol. The smartphone was used as a detector instead of a special large instrument for responding to the glow-type CL emission, and a LOD of 7.2 µM was obtained. Therefore, the proposed sensor expands the application of the glow-type CL in POCT and provides an alternative way for cholesterol detection in clinical diagnosis.


Assuntos
Colesterol/análise , Hidrogéis , Testes Imediatos , Peroxidase do Rábano Silvestre , Humanos , Medições Luminescentes , Luminol
16.
Langmuir ; 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34191526

RESUMO

Emulsion poses a greater challenge for the remediation of oily wastewater, which can be effectively resolved by the metal-organic framework of MIL-100(Fe). The formula Fe3O(H2O)2(OH) (BTC)2 pronounces that MIL-100(Fe) suffers from an intrinsic defect of less charged atoms, which limits its demulsification performance for oil-water separation. Herein, cations of the ionic liquid (1-allyl-3-methylimidazolium, Amim+) were encapsulated in the micropore of MIL-100(Fe) in situ to increase the positive charge density of MIL-100(Fe). Zeta potential demonstrated that the encapsulation of Amim+ increased the positive charge amount of MIL-100(Fe). N2 probe isothermal adsorption/desorption and spectral measurements (X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflection spectroscopy, and attenuated total-reflectance infrared spectroscopy) revealed the host-guest interactions of π···Fe complexation and π···cation electrostatic attraction between Amim+ and MIL-100(Fe) for the composite materials. Amim+ encapsulation greatly enhanced the demulsification performance of MIL-100(Fe) for oil-in-water (O/W) emulsion stabilized by sodium dodecyl sulfate. Amim+-encapsulated MIL-100(Fe) with an Amim+/Fe3+ molar ratio of 1:1 [Amim@MIL-100(Fe)-3:3] showed a demulsification efficiency (DE) of 94% within 30 s, compared with MIL-100(Fe) within 30 min. The maximum DE of Amim@MIL-100(Fe)-3:3 was found to be more than 98% within 5 min. The DE lost by MIL-100(Fe) at the third run decreased from 36 to 17% after encapsulating Amim+. The analysis of surface charge and interfacial tension implied a demulsification mechanism of capturing-fusion, which could be promoted by the greater electrostatic attraction. Finally, the role of Amim+ on the outstanding demulsification performance by Amim+-encapsulated MIL-100(Fe) could be explained by the enhanced nonbonded interaction of electrostatic attraction and van der Waals based on the molecular dynamics simulation.

17.
Water Sci Technol ; 83(11): 2744-2752, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34115628

RESUMO

The aim of this work was to investigate the selective oxidation and direct decolorization of selected organic dyes (Methylene Blue (MB), Rhodamine B (RhB) and Orange II (OrgII)) by persulfate (PDS) without activation. Results show that the decolorization rate of MB was up to 58.0% within 10 minutes, while those of RhB and OrgII were only about 29.6% and 3.0% after 80 minutes, respectively. In comparison with the negligible impacts of pH from 2.0 to 9.0 on MB and OrgII decolorization, RhB decolorization rate obviously varied with the pH changes, and acid pH condition was beneficial for RhB decolorization. Quenching tests implied that the decolorization of dyes by PDS without activation was a nonradical oxidation process rather than sulfate radical oxidation. A plausible mechanism is that the decolorization process is attributed to the charged states of the dyes at different pH conditions, and thus direct electron transfer from dyes to PDS may occur, which is responsible for the bleaching of dyes. This study points out the potential bleaching capability of PDS without activation on cationic dyes, which may have important implications for selective oxidation treatment of dye wastewater.


Assuntos
Corantes , Águas Residuárias , Azul de Metileno , Oxirredução
18.
Adv Mater ; 33(27): e2100770, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34057256

RESUMO

Perovskite solar cells exhibit not only high efficiency under full AM1.5 sunlight, but also have great potential for applications in low-light environments, such as indoors, cloudy conditions, early morning, late evening, etc. Unfortunately, their performance still suffers from severe trap-induced nonradiative recombination, particularly under low-light conditions. Here, a holistic passivation strategy is developed to reduce traps both on the surface and in the bulk of micrometer-thick perovskite film, leading to a record efficiency of 40.1% under 301.6 µW cm-2 warm light-emitting diode (LED) light for low-light solar-cell applications. The involvement of guanidinium into the perovskite bulk film and 2-(4-methoxyphenyl)ethylamine hydrobromide (CH3 O-PEABr) passivation on the perovskite surface synergistically suppresses the trap states. The charge carrier lifetimes of the perovskite film increase by tenfold and fivefold to 981 ns and 8.02 µs at the crystal surface and in its bulk, respectively. The decreased nonradiative recombination loss translates to a high open-circuit voltage (Voc ) of 1.00 V, a high short-circuit current (Jsc ) of 152.10 µA cm-2 , and a fill factor (FF) of 79.52%. Note that this performance also stands as the highest among all photovoltaics measured under indoor light illumination. This work of trap passivation for micrometer-thick perovskite film paves a way for high-performance, self-powered IoT devices.

19.
Brain Pathol ; : e12968, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33960564

RESUMO

Intrauterine growth restriction (IUGR) is a leading cause of perinatal mortality and morbidity, and IUGR survivors are at increased risk of neurodevelopmental deficits. No effective interventions are currently available to improve the structure and function of the IUGR brain before birth. This study investigated the protective effects of low-intensity pulsed ultrasound (LIPUS) on postnatal neurodevelopmental outcomes and brain injury using a rat model of IUGR induced by maternal exposure to dexamethasone (DEX). Pregnant rats were treated with DEX (200 µg/kg, s.c.) and LIPUS daily from gestational day (GD) 14 to 19. Behavioral assessments were performed on the IUGR offspring to examine neurological function. Neuropathology, levels of neurotrophic factors, and CaMKII-Akt-related molecules were assessed in the IUGR brain, and expression of glucose and amino acid transporters and neurotrophic factors were examined in the placenta. Maternal LIPUS treatment increased fetal weight, fetal liver weight, and placental weight following IUGR. LIPUS treatment also increased neuronal number and myelin protein expression in the IUGR brain, and attenuated neurodevelopmental deficits at postnatal day (PND) 18. However, the number of oligodendrocytes or microglia was not affected. These changes were associated with the upregulation of brain-derived neurotrophic factor (BDNF) and placental growth factor (PlGF) protein expression, and enhancement of neuronal CaMKII and Akt activation in the IUGR brain at PND 1. Additionally, LIPUS treatment promoted glucose transporter (GLUT) 1 production and BDNF expression in the placenta, but had no effects on GLUT3 or amino acid transporter expression. Our findings suggest that antenatal LIPUS treatment may reduce IUGR-induced brain injury via enhancing cerebral BDNF/CaMKII/Akt signaling. These data provide new evidence that LIPUS stimulation could be considered for antenatal neuroprotective therapy in IUGR.

20.
Anal Methods ; 13(18): 2092-2098, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33870959

RESUMO

Nanosurface energy transfer (NSET)-based sensors have been widely developed using various pairs of nanomaterials including gold nanoparticles (AuNPs) and quantum dots (QDs). However, a low signal to background ratio is one of the most important problems that researchers are continually trying to solve. Herein, we present a 6-mercaptohexanol (MCH) modified MCH/DNA-Au-QD sensor for the detection of nucleic acids and MUC1. Interestingly, an unexpected effect of MCH was found in enhancing the fluorescence recovery ratio, therefore yielding a higher signal to background ratio. Through further investigation, we perceive the enhancement as a result of lowering of the NSET efficiency between free DNA-AuNPs and free DNA-QDs, which arises from the stretching of adsorbed DNA on the surface of AuNPs. The employment of MCH endowed the sensor with a wider linear range from 5 nM to 120 nM and a relatively lower LOD of 1.19 nM in nucleic acid detection, outperforming the original DNA-Au-QD sensor. Furthermore, the application of the sensor can be further extended to MUC1 detection. This study offers a better understanding of the NSET process between QDs and AuNPs and also initiates a new approach for the performance optimization of analogous NSET-based sensors.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Pontos Quânticos , Transferência de Energia , Ouro
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