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1.
Int J Mol Sci ; 24(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36613569

RESUMO

One in three cancer deaths worldwide are caused by gastric and colorectal cancer malignancies. Although the incidence and fatality rates differ significantly from country to country, the rates of these cancers in East Asian nations such as South Korea and Japan have been increasing each year. Above all, the biggest danger of this disease is how challenging it is to recognize in its early stages. Moreover, most patients with these cancers do not present with any disease symptoms before receiving a definitive diagnosis. Currently, volatile organic compounds (VOCs) are being used for the early prediction of several other diseases, and research has been carried out on these applications. Exhaled VOCs from patients possess remarkable potential as novel biomarkers, and their analysis could be transformative in the prevention and early diagnosis of colon and stomach cancers. VOCs have been spotlighted in recent studies due to their ease of use. Diagnosis on the basis of patient VOC analysis takes less time than methods using gas chromatography, and results in the literature demonstrate that it is possible to determine whether a patient has certain diseases by using organic compounds in their breath as indicators. This study describes how VOCs can be used to precisely detect cancers; as more data are accumulated, the accuracy of this method will increase, and it can be applied in more fields.


Assuntos
Neoplasias Colorretais , Neoplasias Gástricas , Compostos Orgânicos Voláteis , Humanos , Compostos Orgânicos Voláteis/análise , Biomarcadores , Cromatografia Gasosa-Espectrometria de Massas , Neoplasias Gástricas/diagnóstico , Expiração , Testes Respiratórios/métodos , Neoplasias Colorretais/diagnóstico
2.
Int J Mol Sci ; 22(24)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34947978

RESUMO

The downregulation of reactive oxygen species (ROS) facilitates precancerous tumor development, even though increasing the level of ROS can promote metastasis. The transforming growth factor-beta (TGF-ß) signaling pathway plays an anti-tumorigenic role in the initial stages of cancer development but a pro-tumorigenic role in later stages that fosters cancer metastasis. TGF-ß can regulate the production of ROS unambiguously or downregulate antioxidant systems. ROS can influence TGF-ß signaling by enhancing its expression and activation. Thus, TGF-ß signaling and ROS might significantly coordinate cellular processes that cancer cells employ to expedite their malignancy. In cancer cells, interplay between oxidative stress and TGF-ß is critical for tumorigenesis and cancer progression. Thus, both TGF-ß and ROS can develop a robust relationship in cancer cells to augment their malignancy. This review focuses on the appropriate interpretation of this crosstalk between TGF-ß and oxidative stress in cancer, exposing new potential approaches in cancer biology.


Assuntos
Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Estresse Oxidativo , Transdução de Sinais
3.
Heart Surg Forum ; 23(3): E358-E365, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32524973

RESUMO

BACKGROUND: While the surgical correction of moderate aortic stenosis (AS) can be deferred with a watchful waiting according to the present guideline, the clinical outcomes for moderate AS with comorbidity have not extensively been studied. We aimed to explore the factors that would contribute to the outcomes of moderate AS with at least five years of follow-up duration. METHODS: Medical records review identified patients with moderate aortic valve (AV) stenosis from January 2008 and December 2012. Echocardiographic data were gathered, and the final 5-year clinical outcomes, defined as the composite of cardiovascular (CV) death, admission for heart failure (HF) aggravation, and AV replacement, were evaluated. RESULTS: Among 148 patients (mean age, 69.3 years; mean AV area, 1.24 cm2), 79 had adverse outcomes (16 CV deaths, 32 AV replacements, and 31 HF cases), during a mean follow-up of 5.6 years. The event group showed worse dyspnea of NYHA III-IV and a higher frequency of diabetes mellitus (DM). They had a higher frequency of moderate or moderate-to-severe functional mitral regurgitation (MR) and smaller AV area. In the multivariate analysis, DM (HR 2.29, 95% CI 1.03-5.10), moderate or moderate-to-severe MR (HR 4.84, 95% CI 1.66-10.07), and NYHA III-IV (HR 3.84, 95% CI 1.72-8.56) independently were associated with adverse outcomes. CONCLUSIONS: The symptomatic patients with moderate AS had higher events than expected, and early intervention should be considered in case of concomitant MR and DM.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Conduta Expectante/métodos
4.
J Clin Ultrasound ; 48(3): 160-167, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675137

RESUMO

PURPOSE: We explored the potential of tissue velocity imaging (TVI) for prognosis of nonischemic left ventricular (LV) dysfunction (LVD). METHODS: We reviewed 138 nonischemic LVD patients (58 ± 14 years) who underwent both cardiac magnetic resonance (CMR) and echocardiography. Septal and lateral mitral annular TVI data were compared with late gadolinium enhancement (LGE) on CMR. During a mean follow-up of 24 months, recovery (>15%) of LV ejection fraction and clinical outcomes (cardiovascular death and heart failure hospitalization) were assessed. RESULTS: LGE was commonly observed in the basal anteroseptal, inferoseptal, and inferior segments, but infrequently observed in the anterolateral segment. LGE was associated with lower early diastolic, septal (Sep-e' = 5.2 ± 2.0 vs 6.9 ± 2.0 cm/s, P = .031) and lateral (Lat-e' = 7.3 ± 3.0 vs 9.5 ± 2.0 cm/s, P < .001) TVI. The relationship between Lat-e' and anterolateral LGE (area under the curve, AUC 0.834) was much better than that between Sep-e' and inferoseptal LGE (AUC 0.699). The 60 patients with LVD reversibility revealed higher Lat-e' (9.8 ± 2.0 vs 6.7 ± 2.2 cm/s, P < .001) and lower LGE burden (7.3 ± 9.0 vs 22 ± 10%, P < .001), while Lat-e' ≤ 7.8 cm/s appeared unfavorable for 31 events patients. On multivariate analyses, Lat-e' (HR 0.79, 95% CI 0.63-0.99, P = .044) and LVD reversibility (HR 0.53, 95% CI 0.16-0.90, P = .018) were still meaningful together with LGE segments and burden. CONCLUSION: Lat-e' was related with LVD reversibility and a significant predictor of clinical outcomes.


Assuntos
Diástole , Ecocardiografia/métodos , Imageamento por Ressonância Magnética/métodos , Valva Mitral/diagnóstico por imagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste , Feminino , Seguimentos , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda
5.
Eur J Appl Physiol ; 119(5): 1245-1252, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30850877

RESUMO

PURPOSE: To develop accurate and practical prediction models of maximal oxygen consumption (VO2max) using the Young Men's Christian Association (YMCA)-step test in South Korean adults. METHODS: In total, 568 adults (20-66 years) were included in this study. To develop and cross-validate prediction models of VO2max, the total sample was divided into 80% training and 20% testing using a simple random sampling method. VO2max was measured using the maximal-graded exercise treadmill test. Sex, age, 1-min recovery heart rate, body weight, and height were measured as potential predictors. Each test was conducted within a 2- to 3-day interval, ensuring sufficient rest. Preliminary prediction models were developed from training datasets, which were cross-validated using regression analyses and/or repeated-measures analysis of variance. The accuracy of prediction models was evaluated using R2, standard error of estimate (SEE), and mean difference (MD) against a criterion-measured VO2max. RESULTS: The average age and VO2max were 43.5 ± 12.9 years and 39.1 ± 7.5 ml/kg/min, respectively. For model development, three practical models with acceptable accuracy were developed (R2 = 0.56-0.61; SEE = 4.74-5.01). For model cross-validation, significant relationships between the criterion-measured and predicted VO2max were observed in all three models (R2 = 0.56-0.61; SEE = 4.62-4.88). The difference between criterion-measured and predicted VO2max was not significant in the models (MD =- 0.03 to - 0.14). CONCLUSIONS: The prediction models included 3-5 variables as significant predictors of VO2max and had acceptable accuracy in a large sample of South Korean adults. The selected models provide a simple and practical method to estimate VO2max using the YMCA-step test for South Korean adults.


Assuntos
Teste de Esforço/métodos , Consumo de Oxigênio , Adulto , Idoso , Teste de Esforço/normas , Organizações Religiosas/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , República da Coreia
6.
Bioprocess Biosyst Eng ; 42(7): 1195-1204, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30944996

RESUMO

The shortcut biological nitrogen removal (SBNR) process requires less aeration and external carbon due to the oxidization of ammonia into nitrite and its direct denitrification to nitrogen gas during the biological nitrogen removal process. However, this process produces a poor effluent containing NH4+, since the system has to maintain a high free ammonia (FA, NH3) concentration. To overcome this drawback, in this study, the solid retention time (SRT) and the dissolved oxygen (DO) concentration were controlled to achieve both a high ammonia removal rate and nitrite accumulation in the sequencing batch reactor (SBR) process, which can remove nitrogen from wastewater to the desired concentration and provide high free ammonia inhibition and continuous shock loading. When sufficient DO was supplied, nitrite did not accumulate with a 20-day SRT, but the wash-out of nitrite oxidizers in a shorter SRT resulted in a high nitrite accumulation. When DO acted as a limitation, nitrite accumulated at all SRTs. This indicates that nitrite accumulation is more highly influenced by SRT and DO concentration than by FA inhibition. Also, as nitrite accumulated over a 10-day SRT regardless of DO concentration, the accumulation was more highly influenced by SRT than by DO concentration.


Assuntos
Reatores Biológicos , Desnitrificação , Nitrogênio/metabolismo , Águas Residuárias/microbiologia , Microbiologia da Água , Amônia/metabolismo , Nitritos/metabolismo
7.
Nano Lett ; 18(6): 3661-3666, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29761696

RESUMO

The interaction between a magnetic impurity, such as cerium (Ce) atom, and surrounding electrons has been one of the core problems in understanding many-body interaction in solid and its relation to magnetism. Kondo effect, the formation of a new resonant ground state with quenched magnetic moment, provides a general framework to describe many-body interaction in the presence of magnetic impurity. In this Letter, a combined study of angle-resolved photoemission (ARPES) and dynamic mean-field theory (DMFT) on Ce-intercalated graphene shows that Ce-induced localized states near Fermi energy, EF, hybridized with the graphene π-band, exhibit gradual increase in spectral weight upon decreasing temperature. The observed temperature dependence follows the expectations from the Kondo picture in the weak coupling limit. Our results provide a novel insight how Kondo physics emerges in the sea of two-dimensional Dirac electrons.

8.
Bull Environ Contam Toxicol ; 101(2): 185-190, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29915866

RESUMO

Concentrations were measured three times from 2006 to 2013 at major harbors and marine areas along the Korean coast. The Cu concentration in seawater and sediments increased, while the Zn concentration first decreased and then increased. The pattern of increase in Cu concentration with time was consistent with the increased total tonnage of ships moored at the sampling area and with the increased discharge of organic antifouling agents. To confirm the relationship between seawater and marine sediments in heavy metal pollution, all data were arrayed and compared depending on concentrations. The results revealed that the slope of Cu between seawater and marine sediment rapidly decreased, attributed to the increase in the application of copper-based antifouling agents to vessels after the ban on the use of tributyltin in 2008, rather than the contamination caused by industrial areas.


Assuntos
Cobre/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Zinco/análise , Poluição Ambiental/análise , Metais Pesados/análise , Água do Mar/análise , Navios , Poluentes Químicos da Água/análise
9.
Nanotechnology ; 28(20): 205201, 2017 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-28345532

RESUMO

We report europium (Eu)-induced changes in the π-band of graphene (G) formed on the 6H-SiC(0001) surface by a combined study of photoemission measurements and density functional theory (DFT) calculations. Our photoemission data reveal that Eu intercalates upon annealing at 120 °C into the region between the graphene and the buffer layer (BL) to form a G/Eu/BL system, where a band gap of 0.29 eV opens at room temperature. This band gap is found to increase further to 0.48 eV upon cooling down to 60 K. Our DFT calculations suggest that the increased band gap originates from the enhanced hybridization of the graphene π-band with the Eu 4f band due to the increased magnetic ordering upon cooling. These Eu atoms continue to intercalate further down below the BL to produce bilayer graphene (G/BL/Eu) upon annealing at 300 °C. The π-band stemming from the BL then exhibits another band gap of 0.37 eV, which appears to be due to the strong hybridization between the π-band of the BL and the Eu 4f band. The Eu-intercalated graphene thus illustrates an example of versatile band gaps formed under different thermal treatments, which may play a critical role for future applications in graphene-based electronics.

10.
BMC Womens Health ; 17(1): 65, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28830404

RESUMO

BACKGROUND: Many people, although they may recognise the positive effects of exercise, do not exercise regularly owing to lack of time. This study aimed to investigate the effects of prolonged single-session exercise and multiple short sessions of exercise on the risk of metabolic syndrome and the atherogenic index in middle-aged obese women. METHODS: Thirty-six participants were divided into the single-session group, multiple-session group, and control group. The single-session group engaged in one session of treadmill exercise for 30 min a day; the multiple-session group had three sessions of 10 min a day. Both groups exercised 3 days/week for 12 weeks. The control group did not perform any exercise. RESULTS: The single-session group showed decreases in weight (0.97 kg [95% C.I. = 0.09-1.83], p < .05), body mass index (0.43 kg/m2 [95% C.I. = 0.03-0.81], p < .05), and fat mass (1.65 kg, [95% C.I. = 0.78-2.51], p < .01). Systolic blood pressure dropped in the single-session group (6.66 mmHg, [95% C.I. = 1.44-11.88], p < .05), and diastolic blood pressure dropped in the multiple-session group (3.38 mmHg, [95% C.I. = 1.44-5.88], p < .01). High-density lipoprotein cholesterol rose in the single-session group (4.08 mg/dL, [95% C.I. = -8.08-(-)0.07], p < .05) and dropped in the control group (10.75 mg/dL [95% C.I. = 1.95-19.54], p < .01). According to post hoc analysis, high-density lipoprotein cholesterol increased more in the single-session group than the control group (95% C.I. = 0.61-21.88, p < .05). Glucose levels decreased in both the single-session group (16 mg/dL [95% C.I. = 5.64-26.35], p < .01) and the multiple-session group (12.16 mg/dL, [95% C.I. = 2.18-22.14], p < .05). Waist circumference decreased in the single-session group (2.65 cm [95% C.I. = 1.46-3.83], p < .001) and multiple-session group (2.04 cm, [95% C.I. = 1.51-2.73], p < .001). Low-density lipoprotein cholesterol levels rose in both the multiple-session group (-15.79 mg/dL [95% C.I. = -34.24-(-)3.78], p < .05) and the control group (-22.94 mg/dL [95% C.I. = -44.63-(-)1.24], p < .05). The atherogenic index increased in the control group (-1.06 [95% C.I. = -1.69-(-)0.41], p < .01). CONCLUSIONS: The findings indicate that prolonged exercise is superior to multiple short sessions for improving the risk of metabolic syndrome and the atherogenic index in middle-aged obese women. However, multiple short sessions can be recommended as an alternative to prolonged exercise when the goal is to decrease blood glucose or waist circumference.


Assuntos
Índice de Massa Corporal , Exercício Físico/psicologia , Síndrome Metabólica/psicologia , Obesidade/psicologia , Glicemia , Pressão Sanguínea/fisiologia , Peso Corporal , HDL-Colesterol/sangue , Exercício Físico/fisiologia , Feminino , Humanos , Síndrome Metabólica/prevenção & controle , Pessoa de Meia-Idade , Obesidade/prevenção & controle , Circunferência da Cintura
11.
Nanotechnology ; 27(31): 31LT03, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27345294

RESUMO

In order to utilize the superb electronic properties of graphene in future electronic nano-devices, a dependable means of controlling the transport properties of its Dirac electrons has to be devised by forming a tunable band gap. We report on the ion-induced modification of the electronic properties of single-layer graphene (SLG) grown on a SiC(0001) substrate by doping low-energy (5 eV) Li(+) ions. We find the opening of a sizable and tunable band gap up to 0.85 eV, which depends on the Li(+) ion dose as well as the following thermal treatment, and is the largest band gap in the π-band of SLG by any means reported so far. Our Li 1s core-level data together with the valence band suggest that Li(+) ions do not intercalate below the topmost graphene layer, but cause a significant charge asymmetry between the carbon sublattices of SLG to drive the opening of the band gap. We thus provide a route to producing a tunable graphene band gap by doping Li(+) ions, which may play a pivotal role in the utilization of graphene in future graphene-based electronic nano-devices.

12.
Nanotechnology ; 27(48): 485704, 2016 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-27796276

RESUMO

Bilayer graphene (BLG) has an extensive list of industrial applications in graphene-based nanodevices such as energy storage devices, flexible displays, and thermoelectric devices. By doping slow Na+ ions on Li-intercalated BLG, we find significantly improved thermal and electronic properties of BLG by using angle-resolved photoemission and high-resolution core level spectroscopy (HRCLS) with synchrotron photons. Our HRCLS data reveal that the adsorbed Na+ ions on a BLG produced by Li-intercalation through single layer graphene (SLG) spontaneously intercalate below the BLG, and substitute Li atoms to form Na-Si bonds at the SiC interface while preserving the same phase of BLG. This is in sharp contrast with no intercalation of Na+ ions on SLG though neutral Na atoms intercalate. The Na+-induced BLG is found to be stable upon heating up to T = 400 °C, but returns to SLG when heated at T d = 500 °C. The evolution of the π-bands upon doping the Na+ ions followed by thermal annealing shows that the carrier concentration of the π-band may be artificially controlled without damaging the Dirac nature of the π-electrons. The doubled desorption temperature from that (T d = 250 °C) of the Na-intercalated SLG together with the electronic stability of the Na+-intercalated BLG may find more practical and effective applications in advancing graphene-based thermoelectric devices and anode materials for rechargeable batteries.

13.
J Environ Manage ; 166: 94-102, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26496838

RESUMO

There are many disposal and treatment methods for contaminated dredged sediments, depending on their properties. In this study, treatment methods for the remediation of dredged sediments as well as the reduction of pore water generated from dredged sediments were optimized. The efficiency of separation using hydrocyclone as the pre-treatment increased with greater inflow velocity of hydrocyclone, deeper insertion of the vortex finder, and smaller hydrocyclone diameter. In the post-treatment of hydrocyclone overflow, the chemical coagulation and membrane filtration methods had high efficiency with regard to the removal of solid and organic compounds, but the former was less feasible, due to its excessive operation and sludge disposal costs. The membrane filtration was easily applicable in the field, based on its convenience of installation and lower cost of operation despite low removal efficiency of trace organic contaminants.


Assuntos
Recuperação e Remediação Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Esgotos/química , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/isolamento & purificação , Recuperação e Remediação Ambiental/instrumentação , Modelos Teóricos , Instalações de Eliminação de Resíduos/instrumentação
14.
Biotechnol Bioeng ; 112(1): 43-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24981425

RESUMO

To achieve nitrite accumulation for shortcut biological nitrogen removal (SBNR) in a biofilm process, we explored the simultaneous effects of oxygen limitation and free ammonia (FA) and free nitrous acid (FNA) inhibition in the nitrifying biofilm. We used the multi-species nitrifying biofilm model (MSNBM) to identify conditions that should or should not lead to nitrite accumulation, and evaluated the effectiveness of those conditions with experiments in continuous flow biofilm reactors (CFBRs). CFBR experiments were organized into four sets with these expected outcomes based on the MSNBM as follows: (i) Control, giving full nitrification; (ii) oxygen limitation, giving modest long-term nitrite build up; (iii) FA inhibition, giving no long-term nitrite accumulation; and (iv) FA inhibition plus oxygen limitation, giving major long-term nitrite accumulation. Consistent with MSNBM predictions, the experimental results showed that nitrite accumulated in sets 2-4 in the short term, but long-term nitrite accumulation was maintained only in sets 2 and 4, which involved oxygen limitation. Furthermore, nitrite accumulation was substantially greater in set 4, which also included FA inhibition. However, FA inhibition (and accompanying FNA inhibition) alone in set 3 did not maintained long-term nitrite accumulation. Nitrite-oxidizing bacteria (NOB) activity batch tests confirmed that little NOB or only a small fraction of NOB were present in the biofilms for sets 4 and 2, respectively. The experimental data supported the previous modeling results that nitrite accumulation could be achieved with a lower ammonium concentration than had been required for a suspended-growth process. Additional findings were that the biofilm exposed to low dissolved oxygen (DO) limitation and FA inhibition was substantially denser and probably had a lower detachment rate.


Assuntos
Compostos de Amônio/metabolismo , Biofilmes , Reatores Biológicos , Biotecnologia , Nitritos/metabolismo , Oxigênio/metabolismo , Biotecnologia/instrumentação , Biotecnologia/métodos , Desenho de Equipamento , Ácidos Graxos/metabolismo , Oxirredução
15.
Water Sci Technol ; 72(8): 1341-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26465304

RESUMO

CdS doped TiO2 nanotube composite was fabricated by chemical bath deposition, and was characterized by the structural, spectral and photoelectrochemical properties. The results of the structural and spectral properties showed that CdS particles were successfully deposited onto the surface of TiO2 nanotube. It is demonstrated that CdS doped TiO2 nanotube composite improved the light harvesting ability. Power conversion efficiency of about 0.32% was observed. This value is about 2.9 times higher than that of pure TiO2 nanotube. The CdS doped TiO2 nanotube composite possesses relatively higher photocatalytic activity and photodegradation efficiency than that of pure TiO2 nanotube under UV light irradiation, and the degradation efficiency of methyl orange was about 42% at UV intensity of 32 W.


Assuntos
Compostos Azo/efeitos da radiação , Compostos de Cádmio/química , Nanotubos/química , Fotólise , Sulfetos/química , Titânio/química , Compostos Azo/química , Catálise , Luz , Raios Ultravioleta
16.
Environ Technol ; 36(5-8): 1035-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25287910

RESUMO

A two-stage biological aerated/anoxic filter (BAF) system for denitrification-nitrification was developed to increase nitrogen removal in the treatment of municipal wastewater with low carbon:nitrogen (C/N) ratio [Formula: see text]. This system exhibited a high denitrification efficiency (67%), despite the low C/N ratio, and the ratio of reduced nitrate to consumed organic compounds was greater than the theoretical value due to the minimization of the conversion of organic carbon to biomass growth, the maintenance of low levels of dissolved oxygen in recycled water, and the maximization of use of organic carbon biosorbed inside biomass in the denitrification BAF. The maximum rate of nitrogen removal was achieved at a recycle ratio of 170%, and the headloss in two BAFs was maintained after a 24-h backwash. Biological nitrogen removal in a two-stage BAF system was possible in a short hydraulic retention time (1.2 h) because the maximum reaction rates of nitrifiers and denitrifiers in each column were achieved.


Assuntos
Desnitrificação , Nitrificação , Nitrogênio/isolamento & purificação , Purificação da Água , Filtração , Compostos Orgânicos , Oxigênio
17.
J Phys Ther Sci ; 27(5): 1589-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26157269

RESUMO

[Purpose] The lunge Motion that occurs frequently in fencing training and matches results in imbalance of the upper and lower limbs muscles. This research focuses on the improvement of the imbalance that occurs in the national team fencers of the Republic of Korea through specific muscle imbalance improvement training. [Subjects] The subjects of this research were limited to right-handed male fencers. Nine male, right-handed national fencing athletes were selected for this study (4 epee, 5 sabre; age 28.2 ± 2.2 years; height 182.3 ± 4.0 cm; weight 76.5 ± 8.2 kg; experience 12.4 ± 3.0 years). [Methods] The specific muscle imbalance improvement training program was performed for 12 weeks and Pre-Post tests were to evaluate its effect on the experimental group. Measurements comprised anthropometry, test of balance, and movement analysis. [Results] After the training program, mediolateral sway of the nondominant lower limb and the balance scale showed statistically significant improvement. [Conclusion] The specific muscle imbalance improvement training program used in this research was proven to be effective for improving the muscle imbalance of elite fencers.

18.
J Air Waste Manag Assoc ; 64(8): 879-86, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25185390

RESUMO

Commercial activated carbon is a highly effective absorbent that can be used to remove micropollutants from water. As a result, the demand for activated carbon is increasing. In this study, we investigated the optimum manufacturing conditions for producing activated carbon from ligneous wastes generated from food processing. Jujube seeds and walnut shells were selected as raw materials. Carbonization and steam activation were performed in a fixed-bed laboratory electric furnace. To obtain the highest iodine number, the optimum conditions for producing activated carbon from jujube seeds and walnut shells were 2 hr and 1.5 hr (carbonization at 700 degrees C) followed by 1 hr and 0.5 hr (activation at 1000 degrees C), respectively. The surface area and iodine number of activated carbon made from jujube seeds and walnut shells were 1,477 and 1,184 m2/g and 1,450 and 1,200 mg/g, respectively. A pore-distribution analysis revealed that most pores had a pore diameter within or around 30-40 angstroms, and adsorption capacity for surfactants was about 2 times larger than the commercial activated carbon, indicating that waste-based activated carbon can be used as alternative. Implications: Wastes discharged from agricultural and food industries results in a serious environmental problem. A method is proposed to convert food-processing wastes such as jujube seeds and walnut shells into high-grade granular activated carbon. Especially, the performance of jujube seeds as activated carbon is worthy of close attention. There is little research about the application ofjujube seeds. Also, when compared to two commercial carbons (Samchully and Calgon samples), the results show that it is possible to produce high-quality carbon, particularly from jujube seed, using a one-stage, 1,000 degrees C, steam pyrolysis. The preparation of activated carbon from food-processing wastes could increase economic return and reduce pollution.


Assuntos
Carvão Vegetal/química , Recuperação e Remediação Ambiental/métodos , Juglans/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Poluição Química da Água/prevenção & controle , Ziziphus/química , Adsorção , Carvão Vegetal/análise , Cromatografia Líquida de Alta Pressão , Iodo/química , Microscopia Eletrônica de Varredura , Nozes/química , Sementes/química , Vapor/análise , Temperatura , Fatores de Tempo
19.
Environ Technol ; 35(17-20): 2147-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25145166

RESUMO

Membrane distillation (MD) is an emerging desalination technology as an energy-saving alternative to conventional distillation and reverse osmosis method. The selection of appropriate membrane is a prerequisite for the design of an optimized MD process. We proposed a simple approximation method to evaluate the performance of membranes for MD process. Three hollow fibre-type commercial membranes with different thicknesses and pore sizes were tested. Experimental results showed that one membrane was advantageous due to the highest flux, whereas another membrane was due to the lowest feed temperature drop. Regression analyses and multi-stage calculations were used to account for the trade-offeffects of flux and feed temperature drop. The most desirable membrane was selected from tested membranes in terms of the mean flux in a multi-stage process. This method would be useful for the selection of the membranes without complicated simulation techniques.


Assuntos
Destilação/instrumentação , Membranas Artificiais , Água do Mar/química , Cloreto de Sódio/isolamento & purificação , Purificação da Água/instrumentação , Destilação/métodos , Desenho de Equipamento , Análise de Regressão , Cloreto de Sódio/química , Temperatura , Purificação da Água/métodos
20.
Environ Technol ; 35(21-24): 2837-45, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25176488

RESUMO

Electronic wastewater from a semiconductor plant was treated with a pilot-scale four-stage Bardenpho process with membrane system. The system was operated over a 14-month period with an overall hydraulic retention time (HRT) ranging from 9.5 to 30 h. With a few exceptions, the pilot plant consistently treated the electronic wastewater with an average removal efficiency of chemical oxygen demand (COD) and total nitrogen of 97% and 93%, respectively, and achieving effluent quality of COD<15 mg/L, turbidity<1, and silt density index<1. Based on removal efficiencies of the pilot plant, it is possible to lower the HRT to less than 9.5 h to achieve comparable removal efficiencies. An energy-saving configuration where an internal recycle line was omitted and the biomass recycle was rerouted to the pre-anoxic tank, can reduce energy consumption by 8.6% and gave removal efficiencies that were similar to the Bardenpho process. The system achieved pre-anoxic and post-anoxic specific denitrification rate values with a 95% confidence interval of 0.091 ± 0.011 g NO3-N/g MLVSS d and 0.087 ± 0.016 g NO3-N/g MLVSS d, respectively. The effluent from the four-stage Bardenpho with membrane system can be paired with a reverse osmosis system to provide further treatment for reuse purposes.


Assuntos
Reatores Biológicos , Resíduos Industriais , Semicondutores , Eliminação de Resíduos Líquidos/métodos , Análise da Demanda Biológica de Oxigênio , Membranas Artificiais , Nitrogênio/análise , Águas Residuárias , Poluentes Químicos da Água/análise
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