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1.
Environ Sci Technol ; 57(16): 6723-6732, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37043741

RESUMO

Identifying reactive species in advanced oxidation process (AOP) is an essential and intriguing topic that is also challenging and requires continuous efforts. In this study, we exploited a novel AOP technology involving peracetic acid (PAA) activation mediated by a MnII-nitrilotriacetic acid (NTA) complex, which outperformed iron- and cobalt-based PAA activation processes for rapidly degrading phenolic and aniline contaminants from water. The proposed MnII/NTA/PAA system exhibited non-radical oxidation features and could stoichiometrically oxidize sulfoxide probes to the corresponding sulfone products. More importantly, we traced the origin of O atoms from the sulfone products by 18O isotope-tracing experiments and found that PAA was the only oxygen-donor, which is different from the oxidation process mediated by high-valence manganese-oxo intermediates. According to the results of theoretical calculations, we proposed that NTA could tune the coordination circumstance of the MnII center to elongate the O-O bond of the complexed PAA. Additionally, the NTA-MnII-PAA* molecular cluster presented a lower energy gap than the MnII-PAA complex, indicating that the MnII-peroxy complex was more reactive in the presence of NTA. Thus, the NTA-MnII-PAA* complex exhibited a stronger oxidation potential than PAA, which could rapidly oxidize organic contaminants from water. Further, we generalized our findings to the CoII/PAA oxidation process and highlighted that the CoII-PAA* complex might be the overlooked reactive cobalt species. The significance of this work lies in discovering that sometimes the metal-peroxy complex could directly oxidize the contaminants without the further generation of high-valence metal-oxo intermediates and/or radical species through interspecies oxygen and/or electron transfer.


Assuntos
Complexos de Coordenação , Poluentes Químicos da Água , Ácido Peracético , Oxigênio , Metais , Complexos de Coordenação/química , Cobalto , Oxirredução , Água , Peróxido de Hidrogênio
2.
Nucleic Acids Res ; 49(15): 8642-8664, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34352099

RESUMO

Architectural DNA-binding proteins (ADBPs) are abundant constituents of eukaryotic or bacterial chromosomes that bind DNA promiscuously and function in diverse DNA reactions. They generate large conformational changes in DNA upon binding yet can slide along DNA when searching for functional binding sites. Here we investigate the mechanism by which ADBPs diffuse on DNA by single-molecule analyses of mutant proteins rationally chosen to distinguish between rotation-coupled diffusion and DNA surface sliding after transient unbinding from the groove(s). The properties of yeast Nhp6A mutant proteins, combined with molecular dynamics simulations, suggest Nhp6A switches between two binding modes: a static state, in which the HMGB domain is bound within the minor groove with the DNA highly bent, and a mobile state, where the protein is traveling along the DNA surface by means of its flexible N-terminal basic arm. The behaviors of Fis mutants, a bacterial nucleoid-associated helix-turn-helix dimer, are best explained by mobile proteins unbinding from the major groove and diffusing along the DNA surface. Nhp6A, Fis, and bacterial HU are all near exclusively associated with the chromosome, as packaged within the bacterial nucleoid, and can be modeled by three diffusion modes where HU exhibits the fastest and Fis the slowest diffusion.


Assuntos
Proteínas de Ligação a DNA/genética , DNA/genética , Proteínas HMGN/genética , Proteínas Mutantes/genética , Proteínas de Saccharomyces cerevisiae/genética , Cromossomos Bacterianos/genética , Proteínas Mitocondriais/genética , Simulação de Dinâmica Molecular , Ligação Proteica/genética , Saccharomyces cerevisiae/genética , Imagem Individual de Molécula
3.
Environ Res ; 205: 112541, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-34915032

RESUMO

Chemical absorption-biological reduction (CABR) process is an attractive method for NOX removal and Fe(II)EDTA regeneration is important to sustain high NOX removal. In this study a sustainable and eco-friendly sulfur cycling-mediated Fe(II)EDTA regeneration method was incorporated in the integrated biological flue gas desulfurization (FGD)-CABR system. Here, we investigated the NOX and SO2 removal efficiency of the system under three different flue gas flows (100 mL/min, 500 mL/min, and 1000 mL/min) and evaluated the feasibility of chemical Fe(III)EDTA reduction by sulfide in series of batch tests. Our results showed that complete SO2 removal was achieved at all the tested scenarios with sulfide, thiosulfate and S0 accumulation in the solution. Meanwhile, the total removal efficiency of NOX achieved ∼100% in the system, of which 3.2%-23.3% was removed in spray scrubber and 76.7%-96.5% in EGSB reactor along with no N2O emission. The optimal pH and S2-/Fe(III)EDTA for Fe(II)EDTA regeneration and S0 recovery was 8.0 and 1:2. The microbial community analysis results showed that the cooperation of heterotrophic denitrifier (Saprospiraceae_uncultured and Dechloromonas) and iron-reducing bacteria (Klebsiella and Petrimonas) in EGSB reactor and sulfide-oxidizing, nitrate-reducing bacteria (Azoarcus and Pseudarcobacter) in spray scrubber contributed to the efficient removal of NOX in flue gas.


Assuntos
Óxidos de Nitrogênio , Enxofre , Bactérias , Ácido Edético , Óxido Nítrico , Oxirredução , Dióxido de Enxofre
4.
Nucleic Acids Res ; 48(19): 10820-10831, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-32997109

RESUMO

DNA binding proteins rapidly locate their specific DNA targets through a combination of 3D and 1D diffusion mechanisms, with the 1D search involving bidirectional sliding along DNA. However, even in nucleosome-free regions, chromosomes are highly decorated with associated proteins that may block sliding. Here we investigate the ability of the abundant chromatin-associated HMGB protein Nhp6A from Saccharomyces cerevisiae to travel along DNA in the presence of other architectural DNA binding proteins using single-molecule fluorescence microscopy. We observed that 1D diffusion by Nhp6A molecules is retarded by increasing densities of the bacterial proteins Fis and HU and by Nhp6A, indicating these structurally diverse proteins impede Nhp6A mobility on DNA. However, the average travel distances were larger than the average distances between neighboring proteins, implying Nhp6A is able to bypass each of these obstacles. Together with molecular dynamics simulations, our analyses suggest two binding modes: mobile molecules that can bypass barriers as they seek out DNA targets, and near stationary molecules that are associated with neighboring proteins or preferred DNA structures. The ability of mobile Nhp6A molecules to bypass different obstacles on DNA suggests they do not block 1D searches by other DNA binding proteins.


Assuntos
DNA/química , Proteínas HMGN/química , Proteínas de Saccharomyces cerevisiae/química , DNA/metabolismo , Proteínas HMGN/metabolismo , Simulação de Dinâmica Molecular , Movimento (Física) , Ligação Proteica , Proteínas de Saccharomyces cerevisiae/metabolismo , Imagem Individual de Molécula
5.
Hum Factors ; 64(7): 1137-1153, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-33617350

RESUMO

OBJECTIVE: To provide a comprehensive characterization of explosive ordnance disposal (EOD) personal protective equipment (PPE) by evaluating its effects on the human body, specifically the poses, tasks, and conditions under which EOD operations are performed. BACKGROUND: EOD PPE is designed to protect technicians from a blast. The required features of protection make EOD PPE heavy, bulky, poorly ventilated, and difficult to maneuver in. It is not clear how the EOD PPE wearer physiologically adapts to maintain physical and cognitive performance during EOD operations. METHOD: Fourteen participants performed EOD operations including mobility and inspection tasks with and without EOD PPE. Physiological measurement and kinematic data recording were used to record human physiological responses and performance. RESULTS: All physiological measures were significantly higher during the mobility and the inspection tasks when EOD PPE was worn. Participants spent significantly more time to complete the mobility tasks, whereas mixed results were found in the inspection tasks. Higher back muscle activations were seen in participants who performed object manipulation while wearing EOD PPE. CONCLUSION: EOD operations while wearing EOD PPE pose significant physical stress on the human body. The wearer's mobility is impacted by EOD PPE, resulting in decreased speed and higher muscle activations. APPLICATION: The testing and evaluation methodology in this study can be used to benchmark future EOD PPE designs. Identifying hazards posed by EOD PPE lays the groundwork for developing mitigation plans, such as exoskeletons, to reduce physical and cognitive stress caused by EOD PPE on the wearers without compromising their operational performance.


Assuntos
Substâncias Explosivas , Equipamento de Proteção Individual , Corpo Humano , Humanos , Roupa de Proteção , Estresse Fisiológico/fisiologia
6.
Langmuir ; 36(15): 3989-3996, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32259449

RESUMO

The interest in the application of nanofluid in reducing injection pressure has been increasing especially for tight reservoirs. In this work, a new type of hydrophobic carbon nanofluid was prepared and the pressure-reducing performance was investigated. The results of particle size distribution, zeta potential, and transmission electron microscopy image showed that the dispersion of nanofluid was uniform and stable. In addition, the hydrophobic carbon nanofluid showed excellent antitemperature and antisalinity property. The contact angle of oil-wet glass slide can range from 45 to 89° after it adsorbs hydrophobic carbon nanoparticles (HCNPs). The atomic force microscope tests showed that the core surface roughness was reduced about 16.67%. The core flooding tests showed that the pressure-reducing rate of 0.15 wt % HCNP nanofluid can reach 17.00%. HCNPs show good performance in reducing pressure and have a broad application prospect in oil field development.

7.
Dev Med Child Neurol ; 62(9): 1040-1046, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32147834

RESUMO

AIM: To assess the neural and non-neural contributions to spasticity in the impaired ankle of children with cerebral palsy (CP). METHOD: Instrumented tapping of the Achilles tendon was done isometrically to minimize non-neural contributions and elicit neural contributions. Robot-controlled ankle stretching was done at various velocities, including slow stretching, with minimized neural contributions. Spasticity was assessed as having neural (phasic and tonic stretch reflex torque, tendon reflex gain, contraction rate, and half relaxation rate) and non-neural origin (elastic stiffness and viscous damping) in 17 children with CP (six females and 11 males; mean age [SD] 10y 8mo [3y 11mo], range 4y-18y) and 17 typically developing children (six females and 11 males; mean age [SD] 12y 7mo [2y 9mo], range 7y-18y). All torques were normalized to weight×height. RESULTS: Children with CP showed increased phasic and tonic stretch reflex torque (p=0.004 and p=0.001 respectively), tendon reflex gain (p=0.02), contraction rate (p=0.038), half relaxation rate (p=0.02), elastic stiffness (p=0.01), and viscous damping (p=0.01) compared to typically developing children. INTERPRETATION: Controlled stretching and instrumented tendon tapping allow the systematic quantification of various neural and non-neural changes in CP, which can be used to guide impairment-specific treatment. WHAT THIS PAPER ADDS: Ankle spasticity is associated with increased phasic and tonic stretch reflexes, tendon reflex gain, and contraction and half relaxation rates. Ankle spasticity is also associated with increased elastic stiffness and viscous damping.


Contribuciones neuronales y no neuronales a la espasticidad del tobillo en niños con parálisis cerebral OBJETIVO: Evaluar las contribuciones neurales y no neurales a la espasticidad en el tobillo comprometido de niños con parálisis cerebral (PC). MÉTODO: La percusión instrumentada en el tendón de Aquiles se realizó de forma isométrica para minimizar las contribuciones no neurales y un tirón del tendón exagerado, para obtener contribuciones neurales. El estiramiento del tobillo controlado por robot se realizó a varias velocidades, incluido el estiramiento lento, con contribuciones neurales minimizadas. Se evaluó la espasticidad como neural (torque reflejo de estiramiento fásico y tónico, ganancia del reflejo tendinoso, tasa de contracción y media tasa de relajación) y origen no neural (rigidez elástica y amortiguación viscosa) en 17 niños con PC (seis mujeres y 11 varones; edad media [DE] 10a 8m [3a 11m], rango 4a-18a) y 17 niños con desarrollo típico (seis mujeres y 11 hombres; edad media [SD] 12a 7m [2a 9m], rango 7a-18a). Todos los pares de torsion se normalizaron al peso × altura. RESULTADOS: Los niños con PC mostraron un aumento del torque reflejo de estiramiento fásico y tónico (p = 0,004 y p = 0,001 respectivamente), ganancia refleja del tendón (p = 0,02), tasa de contracción (p = 0,038), tasa de relajación media (p = 0,02), rigidez elastica (p = 0,01) y amortiguación viscosa (p = 0,01) en comparación con los niños con desarrollo normal. INTERPRETACIÓN: El estiramiento controlado y la percusión instrumentada del tendón, permiten la cuantificación sistemática de varios cambios neuronales y no neuronales en la PC, que pueden usarse para guiar el tratamiento específico de la discapacidad.


Contribuições neurais e não neurais para a espasticidade do tornozelo em crianças com paralisia cerebral OBJETIVO: Avaliar as contribuições neurais e não-neurais para a espasticidade no tornozelo comprometido de crianças com paralisia cerebral (PC). MÉTODO: O golpeamento instrumentalizado do tendão de Aquiles foi realizado isometricamente para minimizar as contribuições não-neurais e um desvio exagerado do tendão, e assim eliciar as contribuições neurais. O alongamento do tornozelo controlado por um robô foi realizado em várias velocidades, incluindo alongamento lento, com contribuições neurais limitadas. A espasticidade foi avaliada como tendo origem neural (torque do reflexo fásico e tônico, ganho do reflexo tendinoso, taxa de contração, e taxa de meio relaxamento) e não-neural (rigidez elástica e amortecimento viscoso) em 17 crianças com PC (seis do sexo feminino e 11 do sexo masculino; média de idade [DP] 10a 8m [3 11m], variação 4a-18a) e 17 crianças com desenvolvimento típico (seis do sexo feminino e 11 do sexo masculino; média de idade [DP] 12a 7m [2a 9m], variação 7a-18a). Todos os torques foram normalizados para peso x altura. RESULTADOS: Crianças com PC mostraram aumento do torque do reflexo tônico e fásico e (p=0,004 e p=0,001 respectivamente), ganho do reflexo tendinoso (p=0,02), taxa de contração (p=0,038), taxa de meio relaxamento (p=0,02), rigidez elástica (p=0,01), e amortecimento viscoso (p=0,01) em comparação com as crianças com desenvolvimento típico. INTERPRETAÇÃO: O alongamento controlado e o golpeamento instrumentalizado do tendão permitem quantificação sistemática de várias mudanças neurais e não-neurais em PC, as quais podem ser usadas para guiar tratamento específico para a deficiência observada.


Assuntos
Tornozelo/fisiopatologia , Paralisia Cerebral/complicações , Neurônios/fisiologia , Reflexo de Estiramento/fisiologia , Adolescente , Articulação do Tornozelo/fisiopatologia , Criança , Pré-Escolar , Eletromiografia , Feminino , Humanos , Masculino , Contração Muscular/fisiologia , Espasticidade Muscular/complicações , Espasticidade Muscular/fisiopatologia
8.
Langmuir ; 35(37): 12028-12034, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31433661

RESUMO

The self-sustained coalescence-breakup cycles of ferrodrops were investigated for the first time by a high-speed camera under various magnetic fields. Under an axial magnetic field, the upper ferrodrop would deform into a conic shape before coalescing with the bottom ferropeak. Within 0.2 ms after coalescence, the minimum width of the expanding neck obeys a power-law relationship with time, while the exponents increase with the magnetic field and deviate with a decreasing trend in the later coalescence. The cone angle of the upper ferrodrop before coalescence gradually decreases while it increases before breakup with the magnetic field. A critical magnetic field around 35 mT was reported, above which the ferrofluid column undergoes the periodic phenomenon of coalescence and breakup. The frequency for the whole coalescence-breakup cycle increases exponentially with the applied magnetic field. A simplified force balance allows capturing the periodic mechanism involved in this driven harmonic oscillator.

9.
Langmuir ; 34(27): 8015-8023, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29889534

RESUMO

This work aims at studying the effect of electrostatic interactions between cationic surfactants and silica nanoparticles (NPs) on foam stability in porous media. The physio-chemical property of NPs, the gas-liquid interface properties, the foam flow characteristics, together with the stability under different concentrations of surfactant and NPs were investigated and compared. It was found that the affinity of silica NPs to the surface is tunable by variation of surfactant concentrations. NPs and surfactants as a whole assembling at the surface substantially improve the foam stability in static and dynamic tests. These surfactant-modified NPs accumulate at the bubble surface and remain stable under dilution of brine, providing a barrier effectively preventing coalescence. In addition, foam stability is enhanced since the layer of NPs significantly reduces the mass transfer rate, consequently mitigating the Ostwald ripening.

10.
J Phys Ther Sci ; 30(8): 1069-1072, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30154602

RESUMO

[Purpose] To examine muscular demands during self-propelled treadmill walking to provide a potential option for fitness training. [Participants and Methods] Eleven healthy college students were recruited. Participants walked under three conditions: over-ground walking at a self-selected speed, treadmill walking at a self-selected speed, and treadmill walking at a speed comparable to that of over-ground walking. Step lengths and lower extremity muscle activations were recorded while participants walked under the three conditions. [Results] Step lengths were significantly shorter when participants walked on a self-propelled treadmill than when walking over-ground. The spatiotemporal and muscle activations of the gaits varied among the different walking conditions. Muscular demands at the moment of heel-strike were higher around the hip and knee when walking on the self-propelled treadmill than when walking over-ground. [Conclusion] During heel-strike, the lower extremity extensors were activated more on the self-propelled treadmill with an incline, especially at faster speeds, than during over-ground walking. A low-cost, self-propelled treadmill may be a modality for training specific muscles.

11.
Langmuir ; 33(17): 4319-4327, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28391678

RESUMO

Smart wormlike micelles with stimuli-tunable rheological properties may be useful in a variety of applications, such as in molecular devices and sensors. The formation of triplestimuli-responsive systems so far has been a challenging and important issue. In this work, a novel triplestimuli (photo-, pH-, and thermoresponsive) wormlike micelle is constructed with N-cetyl-N-methylmorpholinium bromide and trans-cinnamic acid (CA). The corresponding multiresponsive behaviors of wormlike micellar system were revealed using cryogenic transmission electron microscopy, a rheometer, and 1H NMR. The rheological properties of wormlike micellar system under different temperatures, pH conditions, and UV irradiation times are measured. As confirmed by 1H NMR, chemical structure of a CA molecule can be altered by the multiple stimulation from an exotic environment. We expect it to be a good model for triple-responsive wormlike micelles, which is helpful to understand the mechanism of triple-responsiveness and widen their applications.

12.
Phys Chem Chem Phys ; 19(24): 16047-16056, 2017 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-28597883

RESUMO

The adsorption and viscoelastic properties of a micellar solution of 2-hydroxyl-propanediyl-1,3-bis(hexadecyldimethylammonium bromide), abbreviated as 16-3OH-16, have been investigated by surface tension and rheological measurements. Meanwhile, an aqueous solution of propanediyl-1,3-bis(hexadecyldimethylammonium bromide), abbreviated as 16-3-16, was also examined. From the steady state and oscillatory rheological results, a notable difference in shear viscosities between the two systems was observed. Zeta potentials and size distributions confirm the change in the potentials and hydrodynamic diameters, and these results are in good agreement with the rheological results. The differences of the two solutions were attributed to the effect of the hydroxyl group on the spacer of 16-3OH-16. Molecular dynamic simulations and density functional theory (DFT) calculations were performed to investigate the non-covalent interactions in the solution and the difference between the molecular orbitals and the electrostatic potentials. Our research shows that a more uniform distribution of positive charges around the spacer could result in a more effective electrostatic screening effect between the charged headgroups, and promote the formation of a worm-like micelle. Also, hyperconjugation becomes stronger when the hydroxyl group is introduced on the spacer of the gemini molecule.

13.
Soft Matter ; 12(20): 4549-56, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27094804

RESUMO

Imagine a novel solution that can be switched reversibly from low viscosity to high viscosity with only one additive, upon different commands. To this end, we have developed a simple and effective route to form smart, multi-response wormlike micelles based on a synthesized surfactant, N-cetyl-N,N-diisopropanolammonium bromide (CDIAB). Moreover, we provide new insight into the effects of synergy on this smart wormlike micelle. Rheological measurements were used to study the morphology of the wormlike micelles; (1)H NMR spectroscopy and density functional theory (DFT) calculations were employed to investigate the molecular arrangements and mechanism of the synergy involved in the reversible reactions of pH-response and CO2-response of the micelles in solution. Based on the abovementioned results, it is encouraging to discover that binding energy and electrostatic interaction are the basic driving forces in the formation of wormlike micelles. Moreover, stable viscoelastic behavior was observed in the CDIAB system, with strong binding energy and electrostatic interactions. It is highly anticipated that the synergy observed in this surfactant will be of particular interest due to its novel mechanism and unique properties.

14.
Arch Phys Med Rehabil ; 97(8): 1237-43, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26903143

RESUMO

OBJECTIVE: To examine the outcomes of home-based robot-guided therapy and compare it to laboratory-based robot-guided therapy for the treatment of impaired ankles in children with cerebral palsy. DESIGN: A randomized comparative trial design comparing a home-based training group and a laboratory-based training group. SETTING: Home versus laboratory within a research hospital. PARTICIPANTS: Children (N=41) with cerebral palsy who were at Gross Motor Function Classification System level I, II, or III were randomly assigned to 2 groups. Children in home-based and laboratory-based groups were 8.7±2.8 (n=23) and 10.7±6.0 (n=18) years old, respectively. INTERVENTIONS: Six-week combined passive stretching and active movement intervention of impaired ankle in a laboratory or home environment using a portable rehabilitation robot. MAIN OUTCOME MEASURES: Active dorsiflexion range of motion (as the primary outcome), mobility (6-minute walk test and timed Up and Go test), balance (Pediatric Balance Scale), Selective Motor Control Assessment of the Lower Extremity, Modified Ashworth Scale (MAS) for spasticity, passive range of motion (PROM), strength, and joint stiffness. RESULTS: Significant improvements were found for the home-based group in all biomechanical outcome measures except for PROM and all clinical outcome measures except the MAS. The laboratory-based group also showed significant improvements in all the biomechanical outcome measures and all clinical outcome measures except the MAS. There were no significant differences in the outcome measures between the 2 groups. CONCLUSIONS: These findings suggest that the translation of repetitive, goal-directed, biofeedback training through motivating games from the laboratory to the home environment is feasible. The benefits of home-based robot-guided therapy were similar to those of laboratory-based robot-guided therapy.


Assuntos
Tornozelo/fisiopatologia , Paralisia Cerebral/reabilitação , Serviços de Assistência Domiciliar , Modalidades de Fisioterapia , Robótica , Adolescente , Criança , Feminino , Humanos , Masculino , Limitação da Mobilidade , Força Muscular , Amplitude de Movimento Articular , Índice de Gravidade de Doença
15.
Wei Sheng Wu Xue Bao ; 56(11): 1794-1801, 2016 Nov 04.
Artigo em Zh | MEDLINE | ID: mdl-29741843

RESUMO

Objective: Single-chamber microbial electrolysis cell (SMEC), inoculated by granular sludge from upflow anaerobic sludge bed, can remove Ni(Ⅱ). Therefore, it is of great significance to explore the role microbial community to remove Ni(Ⅱ) in SMEC. Methods: With sodium acetate as substrate, single-factor control method and Illumina high-throughput sequencing were applied to analyze Ni(Ⅱ) removal, as well as microbial community structure and dynamic characteristics in SMEC. Results: Adsorption and microbial functions were the major mechanisms for removing Ni(Ⅱ). In mature single-chamber microbial fuel cell (SMFC), Geobacter sp. of Proteobacteria (91.42%) was dominant on the anode with an abundance of 76.25% whereas Niabella sp. of Bacteroidetes (47.99%) was dominant on the cathode with an abundance of 33.01%, followed by Ochrobactrum sp. of Poribacteria (45.74%) accounting for 10.08%. In SMEC modified from mature SMFC with 12.5 mg-Ni(Ⅱ)/L, the dominant bacteria turned from single Geobacter sp. to Geobacter sp. (41.56%) and Azospirillum sp. (5.97%) on the anode; the dominant bacteria on the cathode turned from Niabella sp. and Ochrobactrum sp. to Acetoanaerobium sp. (19.28%), Dokdonella sp. (16.48%) and Azospirillum sp. (9.49%). Conclusion: Microbial populations in raw sludge were selectively acclimated in the Ni(Ⅱ) removal process of SMEC, and effective microbial communities of electrogenesis and nickel removal were built on the electrode to promote the removal of Ni(Ⅱ) in SMEC.


Assuntos
Bactérias/metabolismo , Fontes de Energia Bioelétrica/microbiologia , Níquel/metabolismo , Bactérias/química , Bactérias/isolamento & purificação , Biodegradação Ambiental , Eletrodos , Eletrólise , Esgotos/microbiologia
16.
J Phys Ther Sci ; 27(9): 2783-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26504293

RESUMO

[Purpose] This study was performed to examine the relationship between physical performance and muscle properties during police cadet training. The study's hypothesis was that improved physical performance brought about by training, would in turn cause a reduction in muscle flexibility. [Subjects and Methods] Fifty-nine police cadets were included in this study. Standard fitness tests and quantitative assessments of muscular biomechanical properties were conducted before, during and after the 20-week cadet training. [Results] General fitness had improved at the end of the police cadet training. There was no significant decrease in muscle flexibility as measured by the Sit-and-Reach test. However, muscle compliance of the non-dominant leg measured by the relaxation coefficient had decreased at the end of the police cadet training. [Conclusion] The increased sit-and-reach distance could be due in part to strengthening of the abdominal muscles. On the other hand, the biomechanical test, which was specific to muscle extensibility, showed a reduction in the relaxation coefficient of the non-dominant leg. Our data suggests that changes in muscle compliance as a result of lower extremity training should be considered. This data may be useful in the design of a training protocol that prevents the potential injuries caused by reduced muscle flexibility.

17.
Sci Total Environ ; 928: 172476, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38621536

RESUMO

The potential applications of nanomaterials in agriculture for alleviating diverse biotic and abiotic stresses have garnered significant attention. The reported mechanisms encompass promoting plant growth and development, alleviating oxidative stress, inducing defense responses, modulating plant-microbe interactions, and more. However, individual studies may not fully uncover the common pathways or distinguish the effects of different nanostructures. We examined Arabidopsis thaliana transcriptomes exposed to biotic, abiotic, and metal or carbon-based nanomaterials, utilizing 24 microarray chipsets and 17 RNA-seq sets. The results showed that: 1) from the perspective of different nanostructures, all metal nanomaterials relieved biotic/abiotic stresses via boosting metal homeostasis, particularly zinc and iron. Carbon nanomaterials induce hormone-related immune responses in the presence of both biotic and abiotic stressors. 2) Considering the distinct features of various nanostructures, metal nanomaterials displayed unique characteristics in seed priming for combating abiotic stresses. In contrast, carbon nanomaterials exhibited attractive features in alleviating water deprivation and acting as signaling amplifiers during biotic stress. 3) For shared pathway analysis, response to hypoxia emerges as the predominant and widely shared regulatory mechanism governing diverse stress responses, including those induced by nanomaterials. By deciphering shared and specific pathways and responses, this research opens new avenues for precision nano-agriculture, offering innovative strategies to optimize plant resilience, improve stress management, and advance sustainable crop production practices.


Assuntos
Arabidopsis , Nanoestruturas , Estresse Fisiológico , Transcriptoma , Arabidopsis/genética , Arabidopsis/fisiologia , Nanoestruturas/toxicidade , Transcriptoma/efeitos dos fármacos
18.
Water Res ; 257: 121684, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38723348

RESUMO

Natural manganese oxides could induce the intermolecular coupling reactions among small-molecule organics in aqueous environments, which is one of the fundamental processes contributing to natural humification. These processes could be simulated to design novel advanced oxidation technology for water purification. In this study, periodate (PI) was selected as the supplementary electron-acceptor for colloidal manganese oxides (Mn(IV)aq) to remove phenolic contaminants from water. By introducing polyferric sulfate (PFS) into the Mn(IV)aq/PI system and exploiting the flocculation potential of Mn(IV)aq, a post-coagulation process was triggered to eliminate soluble manganese after oxidation. Under acidic conditions, periodate exists in the H4IO6- form as an octahedral oxyacid capable of coordinating with Mn(IV)aq to form bidentate complexes or oligomers (Mn(IV)-PI*) as reactive oxidants. The Mn(IV)-PI* complex could induce cross-coupling process between phenolic contaminants, resulting in the formation of oligomerized products ranging from dimers to hexamers. These oligomerized products participate in the coagulation process and become stored within the nascent floc due to their catenulate nature and strong hydrophobicity. Through coordination between Mn(IV)aq and H4IO6-, residual periodate is firmly connected with manganese oxides in the floc after coagulation and could be simultaneously separated from the aqueous phase. This study achieves oxidizing oligomerization through a homogeneous process under mild conditions without additional energy input or heterogeneous catalyst preparation. Compared to traditional mineralization-driven oxidation techniques, the proposed novel cascade processes realize transformation, convergence, and separation of phenolic contaminants with high oxidant utilization efficiency for low-carbon purification.


Assuntos
Oxirredução , Purificação da Água , Purificação da Água/métodos , Óxidos/química , Compostos de Manganês/química , Poluentes Químicos da Água/química , Floculação
19.
J Biomech ; 158: 111738, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37562276

RESUMO

Historically, impaired lower limb function has resulted in heavy health burden and large economic loss in society. Although experts from various fields have put large amounts of effort into overcoming this challenge, there is still not a single standard treatment that can completely restore the lost limb function. During the past half century, with the advancing understanding of human biomechanics and engineering technologies, exoskeletons have achieved certain degrees of success in assisting and rehabilitating patients with loss of limb function, and therefore has been spotlighted in both the medical and engineering fields. In this article, we review the development milestones of lower limb exoskeletons as well as the neuromuscular interactions between the device and wearer throughout the past 50 years. Fifty years ago, the lower-limb exoskeletons just started to be devised. We review several prototypes and present their designs in terms of structure, sensor and control systems. Subsequently, we introduce the development milestones of modern lower limb exoskeletons and discuss the pros and cons of these differentiated devices. In addition, we summarize current important neuromuscular control systems and sensors; and discuss current evidence demonstrating how the exoskeletons may affect neuromuscular control of wearers. In conclusion, based on our review, we point out the possible future direction of combining multiple current technologies to build lower limb exoskeletons that can serve multiple aims.


Assuntos
Exoesqueleto Energizado , Humanos , Extremidade Inferior , Fenômenos Biomecânicos
20.
J Hazard Mater ; 441: 129863, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36088880

RESUMO

Heavy metals (HMs) from smelters pose severe challenges to the environmental soil quality of surrounding farmlands, and threaten human health through the food chain. This study explored the environmental effects of smelting activities on farmland soil, and additionally assessed the enrichment, transfer and health risk of HMs in soil-wheat systems. Multiple characterization results were combined to demonstrate that HMs from smelter waste were transferred to the surrounding soil. It was determined that the enrichment of HMs in soil-wheat systems is mainly controlled by the total HM concentration and pH in soil. Furthermore, the priority pollutant in soil-wheat systems was found to be Cd, and Cd affected the transfer of Cu, Mn and Pb from soil to wheat roots. Interestingly, the -OH stretching, C-H stretching, N-H amide and C-O bending were involved in detoxifying HMs in wheat. The mean values of non-carcinogenic and carcinogenic risks by consuming wheat grain were 9.1, 1.4E-02 (adults) and 11.3, 3.3E-03 (children), respectively, indicating a noteworthy health risk. This study highlighted the critical issues arising from Pb/Zn smelting activities on agricultural soils. Notwithstanding, to ensure food security, the affected regions could opt to follow up on the type of crops grown.


Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Amidas , Cádmio/análise , Criança , China , Monitoramento Ambiental/métodos , Humanos , Chumbo , Metais Pesados/análise , Medição de Risco , Solo/química , Poluentes do Solo/análise , Triticum/química , Zinco
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