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1.
Nano Lett ; 24(18): 5662-5668, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682870

RESUMO

The sensitivity of triboelectric nanogenerators (TENGs) to the surface charge density highlights the significance of triboelectric materials and their modifications. Efforts have been directed toward developing effective strategies for increasing the surface charge density, expanding the potential applications of TENGs. This study proposes the use of irradiation technology for grafting to modify the electron-donating capability of poly(ether sulfone) (PES), thereby affording a dual benefit of enhancing the surface charge density and inducing a shift in the position of PES from negative to positive within the triboelectric series. The TENG based on grafted PES has resulted in a significant 3-fold increase in surface charge density compared to that of pristine PES, reaching 263 µC m-2. The surface charge density can be further increased to 502 µC m-2 through charge pumping. Notably, irradiation technology presents advantages over chemical grafting methods, particularly in terms of sustainability and environmental friendliness. This innovative approach shows great potential in advancing the domain of TENGs.

2.
J Exerc Sci Fit ; 21(1): 138-146, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36606262

RESUMO

Objective: Though multicomponent exercise training was found beneficial in improving the physical functionality, the effects of multicomponent exercise training on muscle oxygenation are still unclear. The purpose of this study was to investigate the effects of multicomponent exercise training on muscle oxygenation in young and older participants. Methods: In this study, 17 young adults (Y) and 18 healthy older adults (E) were recruited to receive a multicomponent exercise training for 12 weeks, 2-3 sessions per week. Muscle oxygenation, muscle strength, and electromyography data were collected and compared pre- and post-training. Muscle oxygen saturation (SpO2) during isometric knee extension tests involving voluntary contraction (VOL) and electrical stimulation (ES) was measured by near-infrared spectroscopy. The SpO2 kinetics in the contraction and recovery phases were calculated using a tangential model to extract ΔSpO2 and inflection time (IF). Results: Muscle strength significantly increased in the post-training (234.31 ± 83.2 N·m, p < 0.05). The post-training ΔSpO2 of the ES in the Y (8.43 ± 5.35%) significantly increased and was higher than that in the E (2.78 ± 3.03%, p < 0.05). In the recovery phase, the post-training IF of VOL (7.07 ± 3.31s) was significantly shorter than that of the pre-training period (8.73 ± 4.46s, p < 0.05). Additionally, the median frequency of electromyography significantly decreased in the post-training period (103.84 ± 21.75 Hz, p < 0.05). Conclusion: The multicomponent exercise training improved the muscle strength, neuromuscular performance, and muscle aerobic function irrespective of age. The primary adaptation of the muscles to the multicomponent exercise training between the two groups varied.

3.
Ann Emerg Med ; 80(5): e69-e70, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36265927
4.
Cancer Sci ; 113(1): 205-220, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34773335

RESUMO

Lung adenocarcinoma (ADC) is the predominant histological type of lung cancer, and radiotherapy is one of the current therapeutic strategies for lung cancer treatment. Unfortunately, biological complexity and cancer heterogeneity contribute to radioresistance development. Karyopherin α2 (KPNA2) is a member of the importin α family that mediates the nucleocytoplasmic transport of cargo proteins. KPNA2 overexpression is observed across cancer tissues of diverse origins. However, the role of KPNA2 in lung cancer radioresistance is unclear. Herein, we demonstrated that high expression of KPNA2 is positively correlated with radioresistance and cancer stem cell (CSC) properties in lung ADC cells. Radioresistant cells exhibited nuclear accumulation of KPNA2 and its cargos (OCT4 and c-MYC). Additionally, KPNA2 knockdown regulated CSC-related gene expression in radioresistant cells. Next-generation sequencing and bioinformatic analysis revealed that STAT1 activation and nuclear phospholipid scramblase 1 (PLSCR1) are involved in KPNA2-mediated radioresistance. Endogenous PLSCR1 interacting with KPNA2 and PLSCR1 knockdown suppressed the radioresistance induced by KPNA2 expression. Both STAT1 and PLSCR1 were found to be positively correlated with dysregulated KPNA2 in radioresistant cells and ADC tissues. We further demonstrated a potential positive feedback loop between PLSCR1 and STAT1 in radioresistant cells, and this PLSCR1-STAT1 loop modulates CSC characteristics. In addition, AKT1 knockdown attenuated the nuclear accumulation of KPNA2 in radioresistant lung cancer cells. Our results collectively support a mechanistic understanding of a novel role for KPNA2 in promoting radioresistance in lung ADC cells.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Núcleo Celular/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Transferência de Fosfolipídeos/metabolismo , Tolerância a Radiação , Fator de Transcrição STAT1/metabolismo , alfa Carioferinas/metabolismo , Adenocarcinoma de Pulmão/genética , Linhagem Celular Tumoral , Retroalimentação Fisiológica , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Técnicas de Inativação de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/genética , Células-Tronco Neoplásicas/metabolismo , Proteínas de Transferência de Fosfolipídeos/genética , Fator de Transcrição STAT1/genética , Regulação para Cima , alfa Carioferinas/genética
5.
Medicine (Baltimore) ; 99(2): e18692, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914069

RESUMO

RATIONALE: Allergic bronchopulmonary aspergillosis (ABPA) complicated with pulmonary thromboembolism (PTE) is rare. This report describes a patient who was diagnosed with ABPA and soon developed PTE. PATIENT CONCERNS: A 64-year-old man was diagnosed with ABPA in hospital for recurrent fever with cough. Two months later, the patient was readmitted to the hospital because of PTE. DIAGNOSES: ABPA was diagnosed during the first hospitalization, and laboratory tests showed an increase in serum IgE and Aspergillus fumigatus-specific IgG. Sputum culture suggested A. fumigatus and high-resolution computed tomography (HRCT) showed inflammation of both lungs and central bronchiectasis. During the second hospitalization, the patient's chest angiography showed PTE. INTERVENTIONS: The patient began treatment with antifungal drugs and corticosteroids, and was discharged from the hospital when his condition improved. Two months after discharge, the patient was treated with anticoagulant drugs due to PTE. OUTCOMES: The patient got better after taking anticoagulant drugs and was discharged from the hospital. The patient appears for regular follow-up visits in our outpatient clinic every 2 months and is currently in good condition. LESSONS: Patients with ABPA may be concurred with PTE. The risk of PTE in ABPA should be assessed in advance and preventive strategies also need to be taken beforehand. Pulmonary artery examination is necessary once it happened.


Assuntos
Aspergilose Broncopulmonar Alérgica/complicações , Embolia Pulmonar/etiologia , Anticoagulantes/uso terapêutico , Antifúngicos/uso terapêutico , Aspergilose Broncopulmonar Alérgica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/tratamento farmacológico
6.
Rapid Commun Mass Spectrom ; 34 Suppl 1: e8578, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31499585

RESUMO

RATIONALE: Accumulating evidence has linked prolonged exposure to heavy metals to cancer occurrence in the urinary system. However, the specific biological mechanisms responsible for the association of heavy metals with the unusually high incidence of upper tract urothelial carcinoma in Taiwan are complex and incompletely understood. METHODS: To elucidate the specific biological mechanism and identify molecular indicators of the unusually high association of upper tract urothelial carcinoma with heavy metal exposure, protein expression following the treatment of T24 human bladder carcinoma and RT4 human bladder papilloma cell line models with arsenic (As) and cadmium (Cd) was studied. Proteomic changes in these cell models were integrated with data from a human bladder cancer (BLCA) tissue proteome to identify possible protein indicators of heavy metal exposure. RESULTS: After mass spectrometry based proteomic analysis and verification by Western blotting procedures, we identified 66 proteins that were up-regulated and 92 proteins that were down-regulated in RT4 cell extracts after treatment with As or Cd. Some 52 proteins were up-regulated and 136 proteins were down-regulated in T24 cell extracts after treatment with Cd. We further confirmed that down-expression of the PML (promyelocytic leukemia) protein was sustained for at least 75 days after exposure of bladder cells to As. Dysregulation of these cellular proteins by As was associated with three biological pathways. Immunohistochemical analyses of paraffin-embedded BLCA tissue slides confirmed that PML protein expression was decreased in BLCA tumor cells compared with adjacent noncancerous epithelial cells. CONCLUSIONS: These data suggest that PML may play an important role in the pathogenesis of BLCA and may be an indicator of heavy metal exposure in bladder cells.


Assuntos
Arsênio/efeitos adversos , Cádmio/efeitos adversos , Proteínas/análise , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/diagnóstico , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Humanos , Mapas de Interação de Proteínas , Proteínas/metabolismo , Proteômica , Transdução de Sinais , Taiwan/epidemiologia , Espectrometria de Massas em Tandem , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/metabolismo
7.
ACS Appl Mater Interfaces ; 12(1): 771-779, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31854975

RESUMO

Hole transport layer NiOx-based inverted perovskite solar cells (PSCs) have advantages of simple fabrication, low temperature, and low cost. Furthermore, the p-type NiOx material compared to that of typical n-type SnOx for PSCs has better photostability potential due to its lower photocatalytic ability. However, the NiOx layer modified by some typical materials show relatively simple functions, which limit the synthesized performance of NiOx-based inverted PSCs. Phenethyl ammonium iodide (PEAI) was introduced to modify the NiOx/perovskite interface, which can synchronously contribute to better crystallinity and stability of the perovskite layer, passivating interface defects, formed quasi-two-dimensional PEA2PbI4 perovskite layers, and superior interface contact properties. The PCEs of PSCs with the PEAI-modified NiOx/perovskite interface was obviously increased from 20.31 from 16.54% compared to that of the reference PSCs. The PSCs with PEAI modification remained 75 and 72% of the original PCE values aging for 10 h at 85 °C and 65 days in a relative humidity of 15%, which are superior to the original PCE values (47 and 51%, respectively) for the reference PSCs. Therefore, PSCs with the PEAI-modified NiOx/perovskite interface show higher PCEs and better thermal stability and moisture resistance.

8.
Am J Cancer Res ; 9(6): 1235-1245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31285955

RESUMO

Systemic chemotherapy is the standard treatment modality for stage IV lung adenocarcinoma patients with EGFR wild-type or unknown mutation status. Recent years, there is increasing evidence showed that selected patients with stage IV disease could benefit from aggressive thoracic radiotherapy. Either pemetrexed or docetaxel, combined with cisplatin, can be used for patients with stage IV lung adenocarcinoma. However, no prospective trials have confirmed that Pem-Cis was superior to Doc-Cis in lung adenocarcinoma. In this randomized phase 2 trial, we evaluated survival outcomes, and toxicity of Pemetrexed-Cisplatin (arm A) or Docetaxel-Cisplatin (arm B) with concurrent IMRT to the primary tumor for stage IV lung adenocarcinoma patients with EGFR wild-type or unknown mutation status. Totally, 101 patients were randomly assigned (50 in arm A and 51 in arm B). Using an intention-to-treat analysis, one-year survival rates were 72.0% and 52.9%, respectively (P=0.020). Progression-free survival was also significantly improved in the arm A (median, 12.6 v 7.5 months, P=0.013). The incidence and severity of acute pneumonitis and esophagitis was similar between two arms. Although more of grade 3 or 4 anemia and thrombocytopenia in arm A, and higher rates grade 3 or 4 neutropenia, and leukopenia were observed in arm B. Pem-Cis first-line chemotherapy with concurrent radiation therapy for stage IV lung adenocarcinoma patients with EGFR wild-type or unknown mutation status represents a potential treatment option with acceptable toxicity and high overall survival rates.

9.
Carbohydr Polym ; 213: 304-310, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30879673

RESUMO

Chitin nanocrystal (ChiNC) was fabricated based on p-toluenesulfonic acid -choline chloride deep eutectic solvent treatment. The obtained ChiNC was about 12-44 nm in width and 206-399 nm in length. The crystalline structure and the functional groups of ChiNC were maintained during the preparation process. Moreover, porcine pancreas lipase (PPL) was successfully immobilized onto the ChiNC to form the immobilized PPL (PPL@ChiNC). The resulting PPL@ChiNC has enzyme loading and activity recovery of 35.6 mg/g and 82.5%, respectively. The thermal stability, pH and temperature adaptabilities of PPL@ChiNC was improved, comparing with free PPL. The demonstrated DES treatment process was efficient for ChiNC preparation and the as-prepared ChiNC exhibited great potentials in biocatalysis and biomedical field.


Assuntos
Benzenossulfonatos/química , Quitina/química , Colina/química , Nanopartículas/química , Quitina/síntese química , Hidrólise , Tamanho da Partícula , Solventes/química , Propriedades de Superfície
10.
RSC Adv ; 9(30): 17308-17317, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35519858

RESUMO

Hierarchically porous carbon (HPC) material based on environmental friendliness biomass has spurred much attention, due to its high surface area and porous structure. Herein, three-dimensional (3D) N,O co-doped HPC (N-O-HPC) was prepared by using a one-step fabrication process of simultaneously carbonizing and activating soybean dregs and used as an electrode for supercapacitors (SCs). The obtained N-O-HPC with 4.8 at% N and 6.1 at% O exhibits a pretty small charge transfer resistance (0.05 Ω) and a large specific capacitance (408 F g-1 at 1 A g-1), due to its 3D hierarchically porous framework structure with extremely large specific surface area (1688 m2 g-1). Moreover, a symmetrical SC assembled with the HPC electrode exhibits an amazingly high energy density (22 W h kg-1 at 450 W kg-1) and a stable long cycling life with only 6% capacitance loss after 5000 cycles in 1 M Na2SO4 solution. This work provides a facile, green, and low-cost way to prepare electrode materials for SCs.

11.
Beilstein J Nanotechnol ; 9: 1686-1694, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977702

RESUMO

Densely populated edge-terminated vertically aligned two-dimensional MoS2 nanosheets (NSs) with thicknesses ranging from 5 to 20 nm were directly synthesized on Mo films deposited on SiO2 by sulfurization. The quality of the obtained NSs was analyzed by scanning electron and transmission electron microscopy, and Raman and X-ray photoelectron spectroscopy. The as-grown NSs were then successfully transferred to the substrates using a wet chemical etching method. The transferred NSs sample showed excellent field-emission properties. A low turn-on field of 3.1 V/µm at a current density of 10 µA/cm2 was measured. The low turn-on field is attributed to the morphology of the NSs exhibiting vertically aligned sheets of MoS2 with sharp and exposed edges. Our findings show that the fabricated MoS2 NSs could have a great potential as robust high-performance electron-emitter material for various applications such as microelectronics and nanoelectronics, flat-panel displays and electron-microscopy emitter tips.

12.
Nanoscale ; 10(12): 5617-5625, 2018 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-29528068

RESUMO

Planar perovskite solar cells (PSCs) that use nickel oxide (NiOx) as a hole transport layer have recently attracted tremendous attention because of their excellent photovoltaic efficiencies and simple fabrication. However, the electrical conductivity of NiOx and the interface contact properties of the NiOx/perovskite layer are always limited for the NiOx layer fabricated at a relatively low annealing temperature. Ferrocenedicarboxylic acid (FDA) was firstly introduced to modify a p-type NiOx hole transport layer in PSCs, which obviously improves the crystallization of the perovskite layer and hole transport and collection abilities and reduces carrier recombination. PSCs with a FDA modified NiOx layer reached a PCE of 18.20%, which is much higher than the PCE (15.13%) of reference PSCs. Furthermore, PSCs with a FDA interfacial modification layer show better UV durability and a hysteresis-free effect and still maintain the original PCE value of 49.8%after being exposed to UV for 24 h. The enhanced performance of the PSCs is attributed to better crystallization of the perovskite layer, the passivation effect of FDA, superior interface contact at the NiOx/perovskite layers and enhancement of the electrical conductivity of the FDA modified NiOx layer. In addition, PSCs with FDA inserted at the interface of the perovskite/PCBM layers can also improve the PCE to 16.62%, indicating that FDA have dual functions to modify p-type and n-type carrier transporting layers.

13.
J Nanosci Nanotechnol ; 18(7): 5063-5073, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442695

RESUMO

We report a simple method for the fabrication of a three-layered plasmonic structure of silicon substrate-Au nanospheres-upconversion particles (UCNPs) that displays up to 101-fold fluorescence enhancement. Monodispersed pure hexagonal-phase NaYF4:Yb,Er core and NaYF4:Yb,Er@NaYF4 core@shell nanocrystals were prepared by a solvothermal method. Two dimensional (2D) assembled Au spheres were prepared on a Si substrate, and then, 2D arrays of UCNPs were deposited on the grown 2D monolayered Au spheres by a self-organizing process. The distance between plasmonic Au NPs and rare-earth (RE) core was finely adjusted by changing the undoped NaYF4 shell thickness. The UC emission enhancement shows a pronounced shell thickness dependence. For the non-plasmonic structured samples, a single peak in upconversion luminescence (UCL) enhancement was observed as the undoped NaYF4 shell thickness increases from 0 nm to 23.0 nm. In contrast, for the plasmonic structured samples, multi-oscillations in UCL enhancement were observed in the undoped NaYF4 shell thickness range of 0-23.0 nm, where the UCL enhancement factors of three bands (521 nm, 540 nm and 654 nm) are high up to 65, 101 and 61, respectively, at 19.6 nm-thick NaYF4 shell. The multi-oscillations in UCL enhancement in the plasmonic samples can be associated with plasmonic coupling between arrays of core-shell UCNPs with various sizes and the underlying 2D Au spheres. The related mechanisms of the UCL enhancements are discussed.

14.
Adv Mater ; 29(44)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29027731

RESUMO

All-inorganic lead halide perovskite quantum dots (IHP QDs) have great potentials in photodetectors. However, the photoresponsivity is limited by the low charge transport efficiency of the IHP QD layers. High-performance phototransistors based on IHP QDs hybridized with organic semiconductors (OSCs) are developed. The smooth surface of IHP QD layers ensures ordered packing of the OSC molecules above them. The OSCs significantly improve the transportation of the photoexcited charges, and the gate effect of the transistor structure significantly enhances the photoresponsivity while simultaneously maintaining high Iphoto /Idark ratio. The devices exhibit outstanding optoelectronic properties in terms of photoresponsivity (1.7 × 104 A W-1 ), detectivity (2.0 × 1014 Jones), external quantum efficiency (67000%), Iphoto /Idark ratio (8.1 × 104 ), and stability (100 d in air). The overall performances of our devices are superior to state-of-the-art IHP photodetectors. The strategy utilized here is general and can be easily applied to many other perovskite photodetectors.

15.
ACS Appl Mater Interfaces ; 9(40): 35200-35208, 2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-28936870

RESUMO

A high-quality perovskite film with interconnected perovskite grains was obtained by incorporating terephthalic acid (TPA) additive into the perovskite precursor solution. The presence of TPA changed the crystallization kinetics of the perovskite film and promoted lateral growth of grains in the vicinity of crystal boundaries. As a result, sheet-shaped perovskite was formed and covered onto the bottom grains, which made some adjacent grains partly merge together to form grains-interconnected perovskite film. Perovskite solar cells (PSCs) with TPA additive exhibited a power conversion efficiency (PCE) of 18.51% with less hysteresis, which is obviously higher than that of pristine cells (15.53%). PSCs without and with TPA additive retain 18 and 51% of the initial PCE value, respectively, aging for 35 days exposed to relative humidity 30% in air without encapsulation. Furthermore, MAPbI3 film with TPA additive shows superior thermal stability to the pristine one under 100 °C baking. The results indicate that the presence of TPA in perovskite film can greatly improve the performance of PSCs as well as their moisture resistance and thermal stability.

16.
Environ Sci Technol ; 51(16): 9363-9370, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28700214

RESUMO

Capacitive neutralization dialysis energy (CNDE) is proposed as a novel energy-harvesting technique that is able to utilize waste acid and alkaline solutions to produce electrical energy. CNDE is a modification based on neutralization dialysis. It was found that a higher NaCl concentration led to a higher open-circuit potential when the concentrations of acid and alkaline solutions were fixed. Upon closing of the circuit, the membrane potential was used as a driving force to move counter ions into the electrical double layers at the electrode-liquid interface, thereby creating an ionic current. Correspondingly, in the external circuit, electrons flow through an external resistor from one electrode to the other, thereby generating electrical energy directly. The influence of external resistances was studied to achieve greater energy extraction, with the maximum output of 110 mW/m2 obtained by employing an external resistance of 5 Ω together with the AC-coated electrode.


Assuntos
Eletricidade , Eletrodos , Íons
17.
Mol Cell Proteomics ; 16(5): 799-811, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28235782

RESUMO

Multiple (selected) reaction monitoring (MRM/SRM) of peptides is a growing technology for target protein quantification because it is more robust, precise, accurate, high-throughput, and multiplex-capable than antibody-based techniques. The technique has been applied clinically to the large-scale quantification of multiple target proteins in different types of fluids. However, previous MRM-based studies have placed less focus on sample-preparation workflow and analytical performance in the precise quantification of proteins in saliva, a noninvasively sampled body fluid. In this study, we evaluated the analytical performance of a simple and robust multiple reaction monitoring (MRM)-based targeted proteomics approach incorporating liquid chromatography with mass spectrometry detection (LC-MRM/MS). This platform was used to quantitatively assess the biomarker potential of a group of 56 salivary proteins that have previously been associated with human cancers. To further enhance the development of this technology for assay of salivary samples, we optimized the workflow for salivary protein digestion and evaluated quantification performance, robustness and technical limitations in analyzing clinical samples. Using a clinically well-characterized cohort of two independent clinical sample sets (total n = 119), we quantitatively characterized these protein biomarker candidates in saliva specimens from controls and oral squamous cell carcinoma (OSCC) patients. The results clearly showed a significant elevation of most targeted proteins in saliva samples from OSCC patients compared with controls. Overall, this platform was capable of assaying the most highly multiplexed panel of salivary protein biomarkers, highlighting the clinical utility of MRM in oral cancer biomarker research.


Assuntos
Biomarcadores Tumorais/metabolismo , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Neoplasias Bucais/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Calibragem , Estudos de Casos e Controles , Humanos , Limite de Detecção , Neoplasias Bucais/diagnóstico , Neoplasias de Células Escamosas/diagnóstico , Neoplasias de Células Escamosas/metabolismo , Reprodutibilidade dos Testes
18.
Environ Sci Technol ; 49(12): 7356-63, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26018772

RESUMO

Composting is widely used for recycling of urban sewage sludge to improve soil properties, which represents a potential pathway of spreading antibiotic resistant bacteria and genes to soils. However, the dynamics of antibiotic resistance genes (ARGs) and the underlying mechanisms during sewage sludge composting were not fully explored. Here, we used high-throughput quantitative PCR and 16S rRNA gene based illumina sequencing to investigate the dynamics of ARGs and bacterial communities during a lab-scale in-vessel composting of sewage sludge. A total of 156 unique ARGs and mobile genetic elements (MGEs) were detected encoding resistance to almost all major classes of antibiotics. ARGs were detected with significantly increased abundance and diversity, and distinct patterns, and were enriched during composting. Marked shifts in bacterial community structures and compositions were observed during composting, with Actinobacteria being the dominant phylum at the late phase of composting. The large proportion of Actinobacteria may partially explain the increase of ARGs during composting. ARGs patterns were significantly correlated with bacterial community structures, suggesting that the dynamic of ARGs was strongly affected by bacterial phylogenetic compositions during composting. These results imply that direct application of sewage sludge compost on field may lead to the spread of abundant ARGs in soils.


Assuntos
Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Esgotos/microbiologia , Solo , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Elementos de DNA Transponíveis/genética , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Dosagem de Genes , Genes Bacterianos , Variação Genética , Concentração de Íons de Hidrogênio , Análise de Componente Principal , RNA Ribossômico 16S/genética
19.
J Chem Phys ; 134(15): 154709, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21513410

RESUMO

The instability of organic monolayer composed of polar molecules at the air-water interface has been a spotlight in interface science for many decades. However, the effect of electrostatic energy contribution to the free energy in the system is still not understood. Herein, we investigate the mechanical and electrical properties by studying the isobaric relaxation process of a dipalmitoyl phosphatidylcholine monolayer on water subphase with various concentrations of divalent ions to reveal the effect of electrostatic energy on thermodynamics and kinetics of the collapse mechanism. Our results demonstrate that electrical energy among the dipolar molecules plays an important role in the stability of monolayer and enhances the formation of micelles into subphase under high pressure. In addition, to confirm the electrostatic energy contribution, the well-known thermal effect on the stability of the film is compared. Hence, the general description of the monolayer free energy with contribution of electrostatic energy is suggested to describe the phase transition.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/química , Ar , Eletricidade Estática , Água/química , Pressão , Propriedades de Superfície , Fatores de Tempo
20.
J Chem Phys ; 130(10): 104706, 2009 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-19292548

RESUMO

The effect of external electrostatic charge on the shapes of liquid condensed (LC) phase domains in monolayer at the air/water interface was investigated. For this reason the thermodynamic properties, domain size, and spontaneous polarization were analyzed by surface pressure-area isotherms, Brewster angle microscopy (BAM), and Maxwell displacement current technique. The analysis indicated magnesium ions preferred to bond with dipalmitoyl phosphatidylcholine negative head group in liquid expanded phase and/or at domain boundary at low ion concentration and got an access to binding with molecules inside of the LC domains for higher ion concentration. Domain size increase characterized by BAM was discussed in respect to the shape equation on the basis of electrostatic energy contribution. Although molecular repulsive force increased by adding of ions into subphase, the growth of domain size exceeded this tendency. Following shape equation analysis it was suggested that this effect corresponded to change in dipole moment orientation represented by increase in spontaneous polarization in normal projection. This demonstrated impact of local electrostatic field on molecular dipoles and free energy of LC domains.

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