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1.
Zhonghua Wai Ke Za Zhi ; 62(2): 155-161, 2024 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-38310384

RESUMO

Objective: To investigate the effect of dexmedetomidine on the intraoperative and early postoperative complications of patients undergoing orthotopic liver transplantation. Methods: This is a retrospective cohort study. The clinical data of 399 patients who underwent orthotopic liver transplantation at the First Affiliated Hospital of Nanjing Medical University from January 2016 to September 2020 were retrospectively collected. There were 319 males and 80 females, aged (50.9±10.2) years (range: 10 to 73 years). These patients were divided into the control group (369 cases) and the dexmedetomidine group (30 cases) according to whether dexmedetomidine was continuously pumped intravenously during the operation until the operation ended. The 1∶2 propensity score matching was used to match the preoperative and intraoperative conditions of the two groups of patients, and the caliper width was 0.2. Outcome indicators included intraoperative postreperfusion syndrome, acute kidney injury and pulmonary complications within 7 days after surgery, length of hospital stay, time of stay in ICU, duration of assisted mechanical ventilation, rate of reintubation, 6-month and 1-year survival and recurrence-free survival rate after surgery. The independent sample t test, χ2 test, Mann-Whitney U test or Fisher exact test was used to statistically analyze the data of the two groups of patients, respectively. Survival curves of overall survival and disease-free-survival were plotted by Kaplan-Meier method, and the survival rate and recurrence-free survival rate were compared by Log-rank test. Results: A total of 78 patients were included after propensity score matching, including 26 in the dexmedetomidine group and 52 in the control group. The incidence of acute kidney injury in the dexmedetomidine group within 7 days after surgery was 0 (0/26), significantly lower than that of the control group (21.2%,11/52)(corrected χ2=4.776, P=0.029). There were no significant differences in the incidence of intraoperative postreperfusion syndrome and pulmonary complications within 7 days after surgery, length of hospital stay, ICU time, the duration of assisted mechanical ventilation, rate of reintubation, 6-month and 1-year survival, and recurrence-free survival rate after surgery between the two groups (all P>0.05). Conclusion: Continuous infusion of dexmedetomidine via intravenous pump during operation may be beneficial in reducing the incidence of acute kidney injury within 7 days after orthotopic liver transplantation.


Assuntos
Injúria Renal Aguda , Dexmedetomidina , Transplante de Fígado , Masculino , Feminino , Humanos , Estudos Retrospectivos , Dexmedetomidina/uso terapêutico , Complicações Pós-Operatórias , Injúria Renal Aguda/tratamento farmacológico
2.
Scand J Rheumatol ; 51(3): 220-229, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34212822

RESUMO

OBJECTIVE: Syndecan-1 (SDC-1), a transmembrane heparin sulphate proteoglycan predominantly expressed on epithelial cells, also exists in a soluble form through ectodomain shedding. SDC-1 expression and shedding may be modulated in the inflammatory milieu of primary Sjögren's syndrome (SS). We investigated SDC-1 expression in minor salivary glands (MSGs) and analysed the association between salivary or plasma levels of SDC-1 and clinical parameters in SS. METHOD: We measured salivary and plasma SDC-1 levels via an enzyme-linked immunosorbent assay and assessed the salivary flow rates (SFRs) in 70 patients with SS and 35 healthy subjects. Disease activity indices, serological markers, salivary gland scintigraphy, and MSG biopsy were evaluated in patients with SS. RESULTS: SDC-1 expression was upregulated on ductal epithelial cells in inflamed salivary glands. Salivary SDC-1 levels in patients significantly exceeded those in healthy subjects [median (interquartile range) 49.0 (20.7-79.1) vs 3.7 (1.7-6.3) ng/mL, p < 0.001] and inversely correlated with SFRs (r = -0.358, p = 0.032) and ejection fractions of the parotid (r = -0.363, p = 0.027) and submandibular (r = -0.485, p = 0.002) glands in salivary gland scintigraphy. Plasma SDC-1 levels were significantly correlated with the EULAR Sjögren's Syndrome Disease Activity Index (r = 0.507, p < 0.001) and EULAR Sjögren's Syndrome Patient Reported Index (r = 0.267, p = 0.033). Focus scores were correlated with salivary SDC-1 levels (r = 0.551, p = 0.004). CONCLUSIONS: Salivary and plasma SDC-1 levels may constitute potential biomarkers for salivary gland function and disease activity, respectively, in SS.


Assuntos
Síndrome de Sjogren , Sindecana-1/metabolismo , Biomarcadores/análise , Humanos , Inflamação , Glândulas Salivares/diagnóstico por imagem , Glândulas Salivares Menores/patologia
3.
Vox Sang ; 112(7): 622-627, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28891069

RESUMO

BACKGROUND AND OBJECTIVES: The Korean Red Cross began nucleic acid amplification testing (NAT) for HIV and HCV in February 2005, and added HBV NAT beginning in June 2012. The current NAT system utilizes a multiplex assay for simultaneous detection of HBV DNA, HCV RNA and HIV-1 RNA. For samples that are reactive in the multiplex assay, we do specific tests for each virus. However, there have been cases of non-discriminated reactive (NDR) results which appear to be the result of non-specific reactions or cross-contamination, although some cases are considered to arise from the presence of low levels of HBV DNA due to occult hepatitis B infection. MATERIALS AND METHODS: We examined the incidence of NDR results in previous donations of some NAT-reactive donors. Additionally, for those donors with NDR results, we performed an HBV core antibody (anti-HBc) assay. RESULTS: From November 2015 to March 2016, there were 408 NAT-reactive donors. Of these, nineteen HBV NAT-reactive donors showed a history of NDR results in the past donations. Seven donors showed NDR results more than once. Of 771 NDR donors, 362 (47·0%) were anti-HBc reactive. CONCLUSION: The NDR donors had a substantially higher rate of anti-HBc reactivity than other blood donors indicating that some with anti-HBc reactivity represent donors with occult HBV. Therefore, the incorporation of an anti-HBc testing for NDR donors could improve blood safety testing for the Korean Red Cross.


Assuntos
Doadores de Sangue , Seleção do Doador/métodos , Anticorpos Anti-Hepatite B/sangue , Hepatite B/sangue , Técnicas de Amplificação de Ácido Nucleico/métodos , Testes Sorológicos/métodos , DNA Viral/sangue , Seleção do Doador/normas , Vírus da Hepatite B/genética , Humanos , Técnicas de Amplificação de Ácido Nucleico/normas , Testes Sorológicos/normas
4.
Br J Anaesth ; 114(3): 437-43, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25416273

RESUMO

BACKGROUND: Coronary computed tomographic angiography (coronary CT) is a non-invasive test for diagnosis of cardiac function. Coronary calcium scores determined by coronary CT are associated with cardiovascular risk factors. However, no studies have investigated the association between coronary calcium scores and cardiovascular complications after liver transplantation (LT). We therefore evaluated the utility of preoperative coronary calcium scores for predicting early postoperative cardiovascular complications in LT recipients. METHODS: Between 2010 and 2012, 443 LT recipients were analysed retrospectively. Preoperative cardiovascular assessments, including coronary CT, were performed. A coronary calcium score >400 was defined as a positive finding. Predictive factors of early postoperative cardiovascular complications were evaluated by univariate and multivariate analyses. Major cardiovascular complications occurring during a period of 1 month after LT were noted. RESULTS: Of the 443 patients, 38 (8.6%) experienced one or more cardiovascular complications. Positive coronary CT findings were seen in 11 (2.5%) patients. In the multivariate analysis, a coronary calcium score >400 {odds ratio (OR)=4.62 [95% confidence interval (CI): 1.14-18.72], P=0.032} and female sex [OR=2.76 (1.37-5.57), P=0.005] were predictive of cardiovascular complications. CONCLUSIONS: A preoperative coronary calcium score of >400 predicted cardiovascular complications occurring 1 month after LT, suggesting that preoperative evaluation of coronary calcium scores could help predict early postoperative cardiovascular complications in LT recipients.


Assuntos
Cálcio/metabolismo , Doenças Cardiovasculares/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/metabolismo , Transplante de Fígado/métodos , Complicações Pós-Operatórias/diagnóstico por imagem , Transplantados/estatística & dados numéricos , Doenças Cardiovasculares/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Complicações Pós-Operatórias/metabolismo , Valor Preditivo dos Testes , Período Pré-Operatório , Estudos Retrospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Tomografia Computadorizada por Raios X/métodos
5.
Vox Sang ; 107(3): 254-60, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24806328

RESUMO

BACKGROUND AND OBJECTIVES: This study was conducted to evaluate the efficacy of pathogen inactivation (PI) in non-leucoreduced platelet-rich plasma-derived platelets suspended in plasma using the Mirasol PRT System and the Intercept Blood System. METHODS: Platelets were pooled using the Acrodose PL system and separated into two aliquots for Mirasol and Intercept treatment. Four replicates of each viral strain were used for the evaluation. For bacteria, both low-titre (45-152 CFU/unit) inoculation and high-titre (7·34-10·18 log CFU/unit) inoculation with two replicates for each bacterial strain were used. Platelets with non-detectable bacterial growth and platelets inoculated with a low titre were stored for 5 days, and culture was performed with the BacT/ALERT system. RESULTS: The inactivation efficacy expressed as log reduction for Mirasol and Intercept systems for viruses was as follows: human immunodeficiency virus 1, ≥4·19 vs. ≥4·23; bovine viral diarrhoea virus, 1·83 vs. ≥6·03; pseudorabies virus, 2·73 vs. ≥5·20; hepatitis A virus, 0·62 vs. 0·76; and porcine parvovirus, 0·28 vs. 0·38. The inactivation efficacy for bacteria was as follows: Escherichia coli, 5·45 vs. ≥9·22; Staphylococcus aureus, 4·26 vs. ≥10·11; and Bacillus subtilis, 5·09 vs. ≥7·74. Postinactivation bacterial growth in platelets inoculated with a low titre of S. aureus or B. subtilis was detected only with Mirasol. CONCLUSION: Pathogen inactivation efficacy of Intercept for enveloped viruses was found to be satisfactory. Mirasol showed satisfactory inactivation efficacy for HIV-1 only. The two selected non-enveloped viruses were not inactivated by both systems. Inactivation efficacy of Intercept was more robust for all bacteria tested at high or low titres.


Assuntos
Plaquetas/microbiologia , Patógenos Transmitidos pelo Sangue/isolamento & purificação , Plasma Rico em Plaquetas/microbiologia , Inativação de Vírus , Bacillus subtilis/isolamento & purificação , Bactérias/isolamento & purificação , Plaquetas/virologia , HIV-1/isolamento & purificação , Humanos , Viabilidade Microbiana , Plasma Rico em Plaquetas/virologia , Staphylococcus aureus/isolamento & purificação , Vírus/isolamento & purificação
6.
Hand Surg Rehabil ; 40(2): 171-176, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33508522

RESUMO

We retrospectively report the outcomes of several cases in which acute Seymour fractures were treated by open reduction of displaced distal bony fragments with concurrent nail repair, following complete incision and drainage without K-wire fixation. Among 21 patients surgically treated between March 2004 and December 2018, the final 12 were evaluated after at least 2 years of follow-up. All children/adolescents presented more than 24 h after the injury. All injuries were unreduced in the emergency department, with typical features of skin disruption around the eponychium/perionychium. Reduction was maintained without a K-wire after repairing the bone-periosteum-nail bed-nail plate of the distal fragment and the corresponding physis-periosteum-germinal matrix-proximal nail-fold of the proximal stump. Dorsal angulation, finger length, postoperative pain on visual analog scale (VAS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, and active range of motion (ROM) were evaluated at the final follow-up. The mean patient age was 9.3 years (range, 3-13 years) and the mean time from injury to surgery was 35 h (range, 28-44 h). Only one child suffered a superficial infection; however, it resolved with 1 week of oral antibiotic treatment. At the final follow-up, mean dorsal angulation was 0.50° ± 1.24°; the length ratio compared with the corresponding contralateral phalanx was 98% (both, P > 0.05). The final pain on VAS, DASH score, and ROM ratio were 0.25 ± 0.45, 0.83 ± 1.34, and 99 ± 2%, respectively. Unreduced Seymour fractures presenting more than 24 h after the injury were treated by proper debridement and reduction of the fracture without the use of a K-wire. However, to determine whether the infection rate is definitively lower, this procedure should be compared with the conventional procedure using a K-wire. Level of Evidence: Therapeutic level IV.


Assuntos
Fixação Intramedular de Fraturas , Fraturas Ósseas , Adolescente , Fios Ortopédicos , Criança , Pré-Escolar , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Humanos , Estudos Retrospectivos
7.
Eur Rev Med Pharmacol Sci ; 25(9): 3519-3529, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34002826

RESUMO

OBJECTIVE: We aimed to analyze clinical characteristics, treatment patterns, and prognosis of patients with reversible cerebral vasoconstriction syndrome (RCVS). MATERIALS AND METHODS: Two investigators independently searched PubMed and EMBASE, and 191 cases were included in this study. Information regarding demographics, triggering factors, brain imaging findings, treatment modalities, recurrence, and clinical outcome was collected. RESULTS: The mean age of the patients was 39.9 years, and 155 (81.2%) were female. The most common triggering factor for RCVS was an exposure to vasoactive substances (41.4%), followed by pregnancy/postpartum (20.9%), and sexual intercourse (10.5%). Multifocal stenosis (84.0%) and beading shape (82.4%) were the leading abnormal findings on angiography, while cerebral ischemic lesions (47.6%) and cerebral hemorrhage (mainly subarachnoid hemorrhage) (35.1%) were the main findings on brain computed tomography (CT)/magnetic resonance imaging (MRI). Calcium channel blockers (nimodipine/verapamil) were the most commonly used medications (44.5%) in the treatment of RCVS. Multivariate analysis identified that RCVS was precipitated by trauma/surgery/procedure (hazard ratio (HR): 3.29, 95% confidence interval (CI) (1.21-8.88), p=0.019), and presence of aphasia/neglect/apraxia during the acute phase of the disease (HR: 3.83, 95% CI (1.33-11.05), p=0.013) were found to be the two independent risk factors for residual neurological deficit after RCVS. CONCLUSIONS: In our systematic review, vasoactive substances were the most frequent triggers for RCVS, which was most commonly accompanied by angiographic findings of multifocal stenotic lesions. Patients with RCVS precipitated by trauma or surgical procedures and those with focal cortical deficits had a higher risk of residual neurological deficits, and these patients should closely be monitored.


Assuntos
Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos da Cefaleia Primários/diagnóstico por imagem , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Humanos , Vasoconstrição
8.
Eur Rev Med Pharmacol Sci ; 25(3): 1536-1547, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33629323

RESUMO

OBJECTIVE: Alzheimer's disease (AD) is a leading cause of years lived with disability in older age, and several cerebrospinal fluid (CSF) markers have been proposed in individual meta-analyses to be associated with AD but field-wide evaluation and scrutiny of the literature is not available. MATERIALS AND METHODS: We performed an umbrella review for the reported associations between CSF biomarkers and AD. Data from available meta-analyses were reanalyzed using both random and fixed effects models. We also estimated between-study heterogeneity, small-study effects, excess significance, and prediction interval. RESULTS: A total of 38 meta-analyses on CSF markers from 11 eligible articles were identified and reanalyzed. In 14 (36%) of the meta-analyses, the summary estimate and the results of the largest study showed non-concordant results in terms of statistical significance. Large heterogeneity (I2≥75%) was observed in 73% and small-study effects under Egger's test were shown in 28% of CSF biomarkers. CONCLUSIONS: Our results suggest that there is an excess of statistically significant results and significant biases in the literature of CSF biomarkers for AD. Therefore, the results of CSF biomarkers should be interpreted with caution.


Assuntos
Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Humanos
9.
Water Sci Technol ; 59(12): 2475-83, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19542654

RESUMO

The purposes of this study were to evaluate the efficiency of acetone removal by electron beam irradiation in groundwater and the effect of various conditions. According to the results, the removal kinetics of acetone were pseudo first-order, and the removal efficiencies were expressed to the (%) removal and G-values. By adding sulfite, it was confirmed that acetone was mainly degraded by the reaction with the hydrated electrons. The presence of nitrate caused the removal of acetone to decrease. But there was no significant effect of alkalinity on the removal of acetone. The effect of the initial pH values (pH 5 to 9) on the acetone removal efficiency was negligible, but the pH value decreases due to the formation of acidic compounds after irradiation. Consequently, the radiation-induced removal reactions of acetone followed the pseudo-first-order kinetic model; in addition to the initial concentration of acetone, nitrate and the absorbed dose were important factors in removing acetone from an aqueous solution using electron beam irradiation. The effects of general pH and alkalinity on the degrading acetone were negligible.


Assuntos
Acetona/química , Elétrons , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos
10.
Ultrason Sonochem ; 51: 160-165, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30389407

RESUMO

A dedicated solidification device and high speed camera were used to capture dendritic fragmentation of pure succinonitrile (SCN) induced by oscillating ultrasonic bubbles. Theoretical analysis of the melting behavior of the dendrite was performed based on local solidification thermodynamics. The dendritic growth or the evolution of the solid-liquid interface is closely related to both thermodynamics of the cavitation bubble and the local geometry of the dendrite. Accordingly, for the first time, a dimensionless scaling formulation was developed by fitting both theoretical and experimental data to determine the variational pressure exerted by the cavitation bubble.

11.
J Nanosci Nanotechnol ; 8(10): 5380-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19198460

RESUMO

Li[Ni(1-x-y)Co(x)Mn(y)]O2 (0.025 < or = x < or = 0.4, 0.015 < or = y < or = 0.25) electrode powders were prepared by a solid-state reaction. The phase purity and R-3m layered structure of the synthesized Li[Ni(1-x-y)Co(x)Mn(y)]O2 materials were confirmed by X-ray diffraction analysis. The particle size of the powder/compounds was decreased with increasing Co and Mn contents to a minimum average particle size of 0.2 approximately 0.3 microm for the LiNi0.35Co0.4Mn0.25O2 powder. A specific capacity of 187 mAh/g was obtained for the LiNi0.35Co0.4Mn0.25O2 electrode with good capacity retention when cycled in the potential region of 3.0-4.6 V with a current density of 20 mA/g at room temperature. Although the structural parameters of the LiNi0.35Co0.4Mn0.25O2 cathode material were similar to those of the LiNil/3CO1/3Mn1/3O2 powder, its specific capacity was higher due to the higher Co contents.

12.
J Nanosci Nanotechnol ; 8(10): 5376-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19198459

RESUMO

LiFePO4 nanocrystalline particles were synthesized using microwave assisted polyol process within a fast reaction time of 20 minutes without any further heating as a post step. The synthesized LiFePO4 nanocrystalline particles showed mono-dispersed rod and orthorhombic-like shapes with a size of 60 approximately 180 nm. The refined X-ray diffraction pattern of the sample was indexed well to the olivine crystal structure (space group: Pnma) without any impurity phases. The LiFePO4 nanocrystalline particles show a capacity of 161 mAh/g in a voltage range of 2.5-4.2 V with a current density of 0.1 mA/cm2 without any observable capacity fading in extended cycles of 100th. A cyclic voltammetry analysis exhibits distinctly sharp peaks corresponding to the typical LiFePO4/FePO4 redox couples and demonstrates a good reversibility of the sample.

14.
Transbound Emerg Dis ; 65(2): 315-320, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29226602

RESUMO

Twenty-five koi (Cyprinus carpio haematopterus) bought from a wholesale fish market in Korea, showed lethargic behaviour and 100% mortality within 20 days. Carp oedema virus (CEV) was detected by PCR in all 25 koi. Results of detailed histopathological and clinical examinations of 17 koi indicated loss of body balance, severe infiltration of inflammatory cells into the inter-lamellar spaces of the gills and vacuolization and inclusion bodies in gill epithelial cells. Sequence analysis of PCR products of these koi showed up to 99% identity to the previously reported sequences, suggesting that the observed mass mortality resulted from koi sleepy disease (KSD) due to CEV infection. To the best of our knowledge, this study is the first report of KSD in the Republic of Korea. Partial sequences of 4a protein from the virus indicated that the present CEV detected in koi from Korea is more closely related to that from the UK and Poland than from Japan. The present findings indicate that the prevalence and spread of KSD must be closely monitored in both European and Asian countries to avoid potential economic losses to the global koi industry.


Assuntos
Carpas/virologia , Doenças Transmissíveis Emergentes/veterinária , Doenças dos Peixes/virologia , Infecções por Poxviridae/veterinária , Poxviridae/isolamento & purificação , Animais , Doenças Transmissíveis Emergentes/patologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/patologia , Genoma Viral/genética , Brânquias/virologia , Reação em Cadeia da Polimerase , Poxviridae/genética , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/patologia , Infecções por Poxviridae/virologia , República da Coreia/epidemiologia
15.
J Nanosci Nanotechnol ; 7(11): 3949-53, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18047094

RESUMO

LiFePO4 nanoparticles were synthesized in various polyol mediums without any further heating. The LiFePO4 samples synthesized in polyol mediums exhibited average sizes of 20, 20, 50, and 50 nm with orthorhombic-like shapes. The XRD patterns were indexed on the basis of an olivine structure (space group : Pnma) except for the sample prepared in EG polyol medium. The LiFePO4 samples prepared in EG, DEG, TEG, and TrEG polyol mediums show the reversible capacity of 120 mA h/g, 144 mA h/g, 159 mA h/g, and 167 mA h/g at current density of 0.1 mA/cm2 with no capacity fading and excellent cycle retentions during extended cycles. Especially, the samples showed the excellent performances at high rate of 30 C and 60 C with high capacity retention. It is a speculation that nanometer size materials (approximately 50 nm) and a uniform size-distribution with highly crystallined phase may affect the excellent performances at high rate current densities.


Assuntos
Cristalização/métodos , Eletroquímica/métodos , Compostos de Ferro/química , Compostos de Magnésio/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Fosfatos/química , Silicatos/química , Impedância Elétrica , Fontes de Energia Elétrica , Eletroquímica/instrumentação , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
16.
J Nanosci Nanotechnol ; 7(11): 3954-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18047095

RESUMO

Ti-based nanoparticles were prepared in polyol mediums of EG (ethylene glycol) and TEG (triethylene glycol), with heating treatment. Ti-based materials of dried power and heated samples showed average sizes of 4, 10, 3, and 8 nm with spherical shapes and monodispersed state, respectively. The XRD patterns of TiO2 and Li4Ti5O12 materials of dried powder and heated samples were indexed to anatase phase TiO2 (space group: I4(1)/amd) and the spinel phase (space group: Fd3m) except for the dried powder sample of Li4Ti5O12, which was corresponded with amorphous-like characteristics from the X-ray diffraction and electron diffraction pattern of Field emission-TEM analysis. The TiO2 and Li4Ti5O12 samples after heat-treated at 500 degrees C exhibited excellent high rate capabilities at a current density of 0.4 mA/cm2 during extended cycles due to their electrochemically beneficial highly crystalline characteristics, nano-sized (approximately 10 nm), and uniform distributions state.


Assuntos
Cristalização/métodos , Eletroquímica/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Polímeros/química , Titânio/química , Impedância Elétrica , Eletroquímica/instrumentação , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
17.
Water Sci Technol ; 56(1): 155-62, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17711011

RESUMO

Diffuse pollution sources along a stream reach are very difficult to both monitor and estimate. In this paper, a systematic method using an optimal estimation algorithm is presented for simultaneous estimation of diffuse pollution and model parameters in a stream water quality model. It was applied with the QUAL2E model to the South Han River in South Korea for optimal estimation of kinetic constants and diffuse loads along the river. Initial calibration results for kinetic constants selected from a sensitivity analysis reveal that diffuse source inputs for nitrogen and phosphorus are essential to satisfy the system mass balance. Diffuse loads for total nitrogen and total phosphorus were estimated by solving the expanded inverse problem. Comparison of kinetic constants estimated simultaneously with diffuse sources to those estimated without diffuse loads, suggests that diffuse sources must be included in the optimization not only for its own estimation but also for adequate estimation of the model parameters. Application of the optimization method to river water quality modeling is discussed in terms of the sensitivity coefficient matrix structure.


Assuntos
Modelos Químicos , Rios/química , Poluição da Água/análise , Abastecimento de Água , Calibragem , Difusão , Cinética
18.
Water Sci Technol ; 55(1-2): 299-306, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17305153

RESUMO

This study was aimed at exploring the reclamation of sewage treatment plant effluent water (SEW) as an alternative water resource. For the oxidation of SEW, an ozone-UV system, based on the results of the combined ozone/UV process performed in our previous study, was set up under practical conditions, including a series type, continuous mode, semi-pilot scale operation (1.5 m3/d). As a result, the serial contact of the ozone and UV reactors showed lower CODCr and TOC removal efficiencies. However, these were greatly enhanced by recycling the water flow of the ozone-UV system at 40Q, as a result of the improvements in the transferred ozone dose in the ozone reactor and the contact efficiency between photons and ozone in the UV reactor, which approached that achieved in the combined ozone/UV process. For the disinfection of SEW, carried out in a syringe-type batch reactor, the increase of instantaneous ozone demand (ozone ID) led to a higher inactivation efficiency, an increased UV transmittance due to ozonation, and an enhanced inactivation rate of E. coli in the UV reactor. Additionally, it was concluded that the ozone/UV process could overcome the limitations of the ozone alone and UV alone processes for the reclamation of sewage effluent water.


Assuntos
Desinfetantes/administração & dosagem , Desinfecção/métodos , Ozônio/administração & dosagem , Esgotos/microbiologia , Raios Ultravioleta , Eliminação de Resíduos Líquidos , Purificação da Água/métodos , Desinfetantes/farmacologia , Oxirredução , Ozônio/farmacologia , Esgotos/química
19.
Water Sci Technol ; 55(12): 213-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17674851

RESUMO

The aim of this study was to investigate some aspects of the performance of electrochemical process as an alternative disinfection strategy, while minimising DBPs, for water purification. The study of electrochemical processes has shown free chlorine to be produced, but smaller amounts of stronger oxidants, such as ozone, hydrogen peroxide and OH radicals (*OH), were also generated. The formation of mixed oxidants increased with increasing electric conductivity, but was limited at conductivities greater than 0.6 mS/cm. Using several microorganisms, such as E. coli and MS2 bacteriophage, inactivation kinetic studies were performed. With the exception of free chlorine, the role of mixed oxidants, especially OH radicals, was investigated for enhancement of the inactivation rate. Additionally, the formation and reduction of DBPs was studied by monitoring the concentration of haloacetic acids (HAAs) during the process.


Assuntos
Cloro/química , Desinfecção/métodos , Butanóis/farmacologia , Condutividade Elétrica , Eletroquímica , Eletrólitos/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Peróxido de Hidrogênio/química , Hidróxidos/química , Levivirus/efeitos dos fármacos , Levivirus/fisiologia , Oxidantes/química , Oxirredução , Ozônio/química
20.
Eur J Surg Oncol ; 43(2): 432-439, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27720564

RESUMO

PURPOSE: The purpose of this study is to evaluate the correlation between lymph node count (LNC) and survival and to evaluate whether lymph node ratio (LNR) which is related to LNC is a better predictor of survival for gastric cancer than the N category of UICC/AJCC through a multi-institutional cohort study. METHODS: The study cohort included 3284 patients from eight institutions. Lower and upper quartiles of LNC were used for comparisons. The cut-off values (0, 0.06, 0.27, and 0.49) for the LNR categories were based on Classification and Regression Trees techniques. Akaike information criteria (AIC) for Cox regression models was used to evaluate goodness of fit between competing predictor variables (LNR vs. N category). RESULTS: The 5-year disease-specific survival (DSS) rates of lower and upper quartiles of LNC were 82.2% and 84.8%. In the subgroup analysis of pN category, the upper quartile of LNC showed better survival than the lower quartile in pN2, pN3a, and pN3b subgroups. Regarding LNR, 5-year DSS of LNR 0, 0-0.06, 0.06-0.27, 0.27-0.49, and >0.49 was 95.3%, 88.7%, 70.6%, 42.7%, and 17.2% respectively. Multivariate analysis showed that pT, pN, LNR, residual tumor status, distant metastasis, and tumor differentiation significantly affected survival. The analysis also confirmed superiority of LNR compared with N category in the AIC analysis. CONCLUSION: Higher LNC correlated with better survival in patients with pN2, pN3a, and pN3b gastric cancer. Our data indicate that LNR is a better predictor of survival than N category of UICC/AJCC.


Assuntos
Metástase Linfática/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Feminino , Humanos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Taxa de Sobrevida
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