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1.
Front Microbiol ; 14: 1086962, 2023.
Article in English | MEDLINE | ID: mdl-36876058

ABSTRACT

Microbial fuel cells (CS-UFC) utilize waste resources containing biodegradable materials that play an essential role in green energy. MFC technology generates "carbon-neutral" bioelectricity and involves a multidisciplinary approach to microbiology. MFCs will play an important role in the harvesting of "green electricity." In this study, a single-chamber urea fuel cell is fabricated that uses these different wastewaters as fuel to generate power. Soil has been used to generate electrical power in microbial fuel cells and exhibited several potential applications to optimize the device; the urea fuel concentration is varied from 0.1 to 0.5 g/mL in a single-chamber compost soil urea fuel cell (CS-UFC). The proposed CS-UFC has a high power density and is suitable for cleaning chemical waste, such as urea, as it generates power by consuming urea-rich waste as fuel. The CS-UFC generates 12 times higher power than conventional fuel cells and exhibits size-dependent behavior. The power generation increases with a shift from the coin cell toward the bulk size. The power density of the CS-UFC is 55.26 mW/m2. This result confirmed that urea fuel significantly affects the power generation of single-chamber CS-UFC. This study aimed to reveal the effect of soil properties on the generated electric power from soil processes using waste, such as urea, urine, and industrial-rich wastewater as fuel. The proposed system is suitable for cleaning chemical waste; moreover, the proposed CS-UFC is a novel, sustainable, cheap, and eco-friendly design system for soil-based bulk-type design for large-scale urea fuel cell applications.

2.
Chemosphere ; 283: 131134, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34157619

ABSTRACT

Magnesium ferrites (MgFe2O4) are important class of ferrites that have been receiving greater attention as promising excellent photocatalyst due to its low cost, wide light spectrum response and environment-friendly nature. However, its poor electronic conductivity and fast charge carrier recombination hinders its electrocatalytical applications. Hence, accelerating charge carriers separation efficiency is important to modify the photoelectrochemical performance of MgFe2O4. Herein, novel Zn ions doped MgFe2O4 nanospheres are fabricated for the first time. Zn ions are doped into MgFe2O4 nanostructures from surface to enhance their charge separation efficiency. The doped MgFe2O4 nanostructures show significant photocatalytic activity and enhanced photocurrent density than that of pristine MgFe2O4.The improved photoelectrocatalytic performance is attributed to doping effect, were Zn ions actually enhance the conductivity. Zn ions enhance the activity of MgFe2O4 and accelerate the charge transfer properties in MgFe2O4. The results highlight that Zn doped MgFe2O4 nanospheres could be a potential candidate for photocatalytic and photoelectrochemical applications.


Subject(s)
Nanostructures , Water , Catalysis , Light , Zinc
3.
Environ Res ; 197: 111128, 2021 06.
Article in English | MEDLINE | ID: mdl-33861975

ABSTRACT

Neodymium (Nd) based perovskite (Nd1-xCoxFeO3) nanostructures were processed to address the rising energy and environment crisis through offering solutions by photocatalytic and photoelectrochemical (PEC) water splitting reactions. The impact of cobalt (Co) ions on the physicochemical properties of Nd-perovskites were studied using X-ray diffraction (XRD), Raman and electron microscopic instruments. The interaction of metal ions was studied in depth via X-ray photoelectron spectroscopy (XPS). Absorption and photoluminescence signals inferred the optical band gap to be lowered and defect states to increase upon Co substitution. Improved photocatalytic efficacy in Nd1-xCoxFeO3 was evaluated by comparative studies using NdFeO3. Secondly, the enhanced conductivities in Nd1-xCoxFeO3 studied via Nyquist plot was found to be advantageous in photoelectrode fabrication for PEC functions. Time-dependent photocurrent density results affirmed the stability in processed devices. Co ions were also inferred to boost the separation of charge carriers effectively. The improved performance in Nd1-xCoxFeO3 nanostructures were well justified to the successful incorporation of Co ions that sway the Nd-O, Co-O and Co-Fe-O bondings and boost the photon absorption and electronic conductivity to facilitate the observed performance.


Subject(s)
Nanostructures , Water , Calcium Compounds , Catalysis , Neodymium , Oxides , Titanium
4.
Sci Rep ; 10(1): 4154, 2020 03 05.
Article in English | MEDLINE | ID: mdl-32139783

ABSTRACT

The acute problem of eutrophication increasing in the environment is due to the increase of industrial wastewater, synthetic nitrogen, urine, and urea. This pollutes groundwater, soil and creates a danger to aquatic life. Therefore, it is advantageous to use these waste materials in the form of urea as fuel to generate power using Microbial Fuel Cell (MFC). In this work, we studied the compost soil MFC(CSMFC) unlike typical MFC with urea from the compost as fuel and graphite as a functional electrode. The electrochemical techniques such as Cyclic Voltammetry, Chronoamperometry are used to characterise CSMFC. It is observed that the CSMFC in which the compost consists of urea concertation of 0.5 g/ml produces maximum power. Moreover, IV measurement is carried out using polarization curves in order to study its sustainability and scalability. Bacterial studies were also playing a significant role in power generation. The sustainability study revealed that urea is consumed in CSMFC to generate power. This study confirmed that urea has a profound effect on the power generation from the CSMFC. Our focus is to get power from the soil processes in future by using waste like urine, industrial wastewater, which contains much amount of urea.

5.
Clin Radiol ; 74(5): 406.e19-406.e27, 2019 05.
Article in English | MEDLINE | ID: mdl-30826002

ABSTRACT

AIM: To evaluate the correlation between the apparent diffusion coefficient (ADC) and various histopathological parameters in small hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: In 143 surgically resected small HCCs, the mean and minimum ADC values, tumour-to-liver ADC ratio, and normalised ADC (ADC of the HCC/ADC of the spleen) were correlated to the tumour grade, microvascular invasion (MVI), cellularity, fatty change, degree of fibrosis, and lymphocytic infiltration using linear regression analysis, the Wilcoxon rank sum test, or Spearman's rank correlation. RESULTS: No significant correlation was found between the ADC parameters and tumour grade. In the univariate analysis, the ADC ratio of the tumour was significantly correlated with MVI as well as the degree of fibrosis and lymphocyte infiltration of the HCC (p=0.017, 0.042, and 0.002, respectively). The ADC of the tumour was significantly correlated with the degree of lymphocyte infiltration of the HCC (p=0.049). In the multivariate analysis, the ADC ratio of the tumour was an independent parameter for MVI and the degree of lymphocyte infiltration of the HCC (p=0.034 and <0.001, respectively), and the ADC of the tumour was an independent parameter for the degree of lymphocyte infiltration of the HCC (p=0.009). There was no significant correlation between the other ADCs and pathological tumour parameters. CONCLUSION: The tumour grade of small HCCs was not correlated with ADC parameters. The tumour-to-liver ADC ratio was a significant independent parameter for the degree of lymphocyte infiltration and MVI of small HCCs.


Subject(s)
Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Microvessels/pathology , Vascular Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Diffusion Magnetic Resonance Imaging/methods , Female , Humans , Liver Cirrhosis/pathology , Male , Middle Aged , Neoplasm Grading , Neoplasm Invasiveness , Retrospective Studies
6.
J Colloid Interface Sci ; 540: 476-485, 2019 Mar 22.
Article in English | MEDLINE | ID: mdl-30669105

ABSTRACT

Recently there has been immense interest in the exploration of richly available two-dimensional non-toxic layered material such as tin disulfide (SnS2) for potential employment in energy and environmental needs. In this regard, we report on the synthesis of few-layered Sn1-xMgxS2 nanosheets through a facile one-step hydrothermal route to address all such functions concerning photocatalysis and photoelectrochemical conversion. The crystalline order and structure of processed layered Sn1-xMgxS2 were initially found to exhibit a strong influence on their physicochemical properties. Their optical properties attest the Mg doping in SnS2 to benefit us with enhanced visible-light absorption via red-shift in their absorption edge. In the photoluminescence spectrum the emissions observed along visible and red region signifies the association of Mg related trap states in Sn1-xMgxS2. Next, the photocurrent and electrochemical impedance spectroscopic results revealed the Mg doping to promote the effective charge transfer process (which was beneficial to enhance their photocatalytic activity). Consequently, the layered Sn0.98Mg0.02S2 made photoanodes displayed 1.7 fold higher photocurrent density under simulated solar radiation with respect to their undoped counterpart. Furthermore, the layered Sn0.98Mg0.02S2 nanosheets exhibits enhanced visible light decomposition of organic dye while compared with pristine SnS2 nanosheets. The value of rate constants obtained for the Sn0.98Mg0.02S2 nanosheets was found to be 1.4 times higher than that of pristine SnS2. Finally, the results obtained through the present study projects the huge potential of layered Sn0.98Mg0.02S2 nanosheets for future multifunctional applications.

7.
Hand Surg Rehabil ; 38(1): 59-66, 2019 02.
Article in English | MEDLINE | ID: mdl-30401613

ABSTRACT

Hand osteoarthritis reduces a person's ability to perform work activities and return to their occupation. We investigated the effects of a finger exercise program on hand grip strength, pain, physical function, and stiffness in automobile manufacturing workers with hand osteoarthritis. This randomized controlled trial was conducted on 29 subjects. Fifteen experimental subjects received a finger exercise program with paraffin baths, while 14 control subjects received only paraffin baths. Hand grip strength, pain, physical function, and stiffness were assessed at baseline and 8 weeks later. In the experimental group, hand grip strength (P < 0.001) and Australian/Canadian osteoarthritis hand index (AUSCAN) scores (pain, P < 0.001; stiffness, P < 0.001; physical function, P < 0.001) were significantly improved by 3.52 ± 2.03, 21.6 ± 8.3 (pain), 16.8 ± 10.21 (stiffness), and 13.86 ± 4.54 (physical function) compared with preintervention values. In the control group, hand grip strength (P = 0.004) and AUSCAN scores (pain, P < 0.001; stiffness, P = 0.019; physical function, P < 0.001) were significantly improved by 0.57 ± 0.62, 7.85 ± 5.46 (pain) 11.42 ± 7.18 (stiffness), and 10.28 ± 14.41 (physical function) compared with preintervention values. Significant differences between groups were found for postintervention hand grip strength (P = 0.015) and AUSCAN index subscale scores (pain, P < 0.001; physical function, P = 0.020). A combined finger exercise and paraffin bath program is effective in reducing pain, improving physical function, and increasing hand grip strength in workers with hand osteoarthritis.


Subject(s)
Exercise Therapy , Hand/physiopathology , Osteoarthritis/rehabilitation , Automobiles , Baths , Combined Modality Therapy , Disability Evaluation , Hand Strength , Humans , Middle Aged , Occupations , Osteoarthritis/physiopathology , Pain Measurement , Paraffin , Range of Motion, Articular
8.
Clin Radiol ; 73(7): 676.e15-676.e24, 2018 07.
Article in English | MEDLINE | ID: mdl-29709236

ABSTRACT

AIM: To assess the long-term therapeutic outcomes of radiofrequency ablation (RFA) versus surgical resection (SR) as a first-line treatment for patients meeting the Milan criteria with multiple hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between January 2004 and December 2009, among 3,441 patients with treatment-naive HCCs, 88 patients meeting the Milan criteria with multiple HCCs (Barcelona Clinic Liver Cancer [BCLC] A stage) who underwent either RFA (n=62) or SR (n=26) were included. Recurrence-free survival (RFS) and overall survival (OS) rates were compared by using propensity score matching. In addition, multivariate analysis was performed for assess the prognostic factor. RESULTS: Matching yielded 20 matched pairs of patients. In the two matched groups, the RFS rates were 30% and 30% at 5- and 10-years, respectively, in the RFA group and 60% and 48.6% in the SR group (p=0.054). The corresponding OS rates were 63.3% and 46.1% in the RFA group and 100% and 73.6% in the SR group, respectively (p=0.061). In multivariate analysis, treatment type was independently associated with RFS (hazard ratio [HR]=0.51; p=0.043) whereas it was not a statistically significant factor for OS (HR=0.50; p=0.088). CONCLUSION: In patients meeting the Milan criteria with multiple HCCs (BCLC A stage), SR may provide better RFS compared to RFA.


Subject(s)
Carcinoma, Hepatocellular/surgery , Liver Neoplasms/surgery , Radiofrequency Ablation/methods , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Hepatectomy , Humans , Liver/surgery , Male , Middle Aged , Retrospective Studies , Survival Rate , Treatment Outcome
9.
Clin Radiol ; 73(6): 564-573, 2018 06.
Article in English | MEDLINE | ID: mdl-29519500

ABSTRACT

AIM: To determine the preoperative computed tomography (CT) parameters that predict portal vein/superior mesenteric vein (PV-SMV) invasion in patients with pancreatic head cancer, and to assess whether PV-SMV invasion affects patient survival. MATERIALS AND METHODS: Sixty patients with PV-SMV invasion, and 60 randomly selected patients without it, who had undergone preoperative CT and subsequent surgery for pancreatic head cancer were enrolled. The following CT parameters were evaluated using multivariate logistic regression and receiver operating characteristic analyses to predict vessel invasion (tumour size and margin, length of involved vessel, distance from the tumour to the vessel, vessel irregularity, the teardrop sign, and tumour-vein interface [TVI]). The Cox proportional hazard model was used to evaluate the effects of PV-SMV invasion on survival. RESULTS: In multivariate analysis, tumour size (odds ratio [OR]=1.99) and TVI (OR=3.79 [≤90°], 20.66 [>90°, ≤180°], and 47.24 [>180°]) were independent CT predictors of PV-SMV invasion (p<0.05); they achieved a sensitivity of 87%, a specificity of 75%, and an accuracy of 81%; however, PV-SMV invasion did not affect patient survival after surgery (p=0.374). CONCLUSION: In patients with pancreatic head cancer, preoperative CT parameters can predict PV-SMV invasion with high accuracy. PV-SMV invasion did not affect treatment outcome after surgery.


Subject(s)
Mesenteric Veins/pathology , Pancreatic Neoplasms/pathology , Portal Vein/pathology , Vascular Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Female , Humans , Male , Mesenteric Veins/diagnostic imaging , Middle Aged , Neoplasm Invasiveness , Organ Sparing Treatments/methods , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/surgery , Pancreaticoduodenectomy/methods , Portal Vein/diagnostic imaging , Preoperative Care/methods , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome , Tumor Burden , Vascular Neoplasms/diagnostic imaging , Pancreatic Neoplasms
10.
Clin Radiol ; 73(2): 216.e1-216.e8, 2018 02.
Article in English | MEDLINE | ID: mdl-28859852

ABSTRACT

AIM: To compare the long-term therapeutic outcomes of repeated radiofrequency ablation (RFA) with that of transarterial chemoembolisation (TACE) in patients with local tumour progression (LTP) after initial RFA treatment for hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between July 2006 and February 2012, 713 patients underwent RFA for single HCC as a first-line treatment. Fifty-eight patients who showed LTP as initial tumour recurrence post-RFA treatment were included. Patients were treated with either repeated RFA (n=33) or TACE (n=25). TACE was performed as an alternative therapeutic option when repeated RFA was not feasible based on the planning ultrasonography. Recurrence-free and overall survival rates were estimated using the Kaplan-Meier method. Prognostic factors for outcomes were evaluated using the Cox proportional hazards model. RESULTS: Both groups did not show significant differences in terms of baseline characteristics, with the exception being the proportion of subphrenic tumours (p=0.031). The RFA and TACE groups did not differ significantly in their 5-year recurrence-free and overall survival rates (17% versus 10.7% and 72.7% versus 51.9%, respectively, with all p-values >0.05). In addition, multivariate analyses revealed that type of treatment was not associated with recurrence-free or overall survival in patients with post-RFA LTP. CONCLUSION: TACE is an effective treatment, comparable to repeated RFA, in patients with LTP after initial RFA when repeated RFA is not feasible.


Subject(s)
Carcinoma, Hepatocellular/therapy , Catheter Ablation/methods , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Aged , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/surgery , Disease-Free Survival , Female , Follow-Up Studies , Humans , Liver/diagnostic imaging , Liver/surgery , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Male , Middle Aged , Retreatment , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome , Ultrasonography
11.
Clin Radiol ; 73(3): 321.e1-321.e10, 2018 03.
Article in English | MEDLINE | ID: mdl-29221719

ABSTRACT

AIM: To integrate various criteria for borderline resectable pancreatic cancer (BRPC) based on radiological parameters using classification tree analysis. MATERIALS AND METHODS: The institutional review board approved this retrospective study and waived the requirement for informed consent. Two hundred and thirty-five tumour-vein interfaces and 67 tumour-artery interfaces in 245 patients with surgically confirmed pancreatic ductal adenocarcinoma who underwent both preoperative computed tomography (CT) and magnetic resonance imaging (MRI) were assessed by two independent readers. Radiological parameters for evaluation of the tumour-vascular interface were boundary, length of interface, degree of circumferential interface, and contour deformity of affected vessels. Classification tree analysis was performed to determine parameters associated with vascular invasion using pathological and surgical results as the reference standard. RESULTS: In the classification tree analysis for the tumour-vein interface, contour deformity and degree of circumferential interface were the first and second determining factors, respectively, for both surgical and pathological vascular invasion. For the tumour-artery interface, boundary and degree of circumferential interface were the first and second determining factors for surgical invasion, while contour deformity and length of interface were the first and second determining factors for pathological invasion. The BRPC group of modified criteria arbitrarily formed based on the results had similar surgical (74.1-81.6%) and pathological (54.3-63.3%) venous invasion compared to that of the National Comprehensive Cancer Network (NCCN) criteria, and the lowest surgical (33.3%) and pathological (6.7%) arterial invasion compared with those in previously established criteria for BRPC (43.3-55.6% and 22.2-26.1%, respectively). CONCLUSION: Various criteria for BRPCs were integrated using classification tree analysis, and a modified criterion for BRPC, which provides satisfactory results, was established.


Subject(s)
Carcinoma, Pancreatic Ductal/diagnostic imaging , Decision Trees , Neovascularization, Pathologic/diagnostic imaging , Pancreatic Neoplasms/diagnostic imaging , Vascular Neoplasms/diagnostic imaging , Aged , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/surgery , Contrast Media , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neoplasm Grading , Neoplasm Invasiveness , Neovascularization, Pathologic/pathology , Neovascularization, Pathologic/surgery , Pancreatectomy/methods , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome , Vascular Neoplasms/pathology , Vascular Neoplasms/surgery
12.
Ultrason Sonochem ; 39: 414-419, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28732963

ABSTRACT

Colloidal zinc telluride (ZnTe) nanostructures were successfully processed through a simple and facile ultrasonic (sonochemical) treatment for photoelectronic applications. The particle-like morphological features, phase and nature of valence state of various metal ions existing in ZnTe were examined using electron and X-ray photoelectron spectroscopic tools. Raman spectroscopic measurements revealed the dominance of exciton-phonon coupling and occurrence of TeO2 traces in ZnTe through the corresponding vibrations. Optical bandgap of the ZnTe suspension was estimated to be around 2.15eV, authenticating the direct allowed transitions. The p-type electrical conductivity and charge carrier density of ZnTe were additionally estimated from the Bode, Nyquist and Mott-Schottky type impedance plots. The photoelectrical properties of ZnTe were investigated by fabricating p-ZnTe/n-Si heterostructures and studying their corresponding current-voltage characteristics under dark and white light illumination. The diodes revealed excellent rectifying behaviour with significant increase in reverse current under illumination. The stability of the devices were also affirmed through the time-dependent photoresponse characteristics, which actually suggested the improved and effective separation of photo generated electron hole pairs across the integrated heterojunctions. The obtained results also augment the potential of sonochemically processed ZnTe for application in photo detection and sensor related functions.

13.
Clin Radiol ; 72(6): 473-481, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28258741

ABSTRACT

AIM: To assess the significant factors on rectal magnetic resonance imaging (MRI) to predict the likelihood of a diagnosis of metastasis for indeterminate hepatic lesions found at computed tomography (CT) in patients with rectal cancer. MATERIALS AND METHODS: A total of 207 patients with rectal cancer who underwent preoperative contrast-enhanced abdominopelvic CT, and rectal and liver MRI were included. Univariate analysis and multivariate logistic regression were used to evaluate the determining factors for the significance of indeterminate hepatic lesions on CT in patients with rectal cancer. RESULTS: Hepatic metastases were diagnosed in 29 (20.9%) of 139 patients who had indeterminate hepatic lesions on preoperative CT obtained for rectal cancer. On univariate analysis, carcinoembryonic antigen level, N stage, mesorectal fascia (MRF) invasion, diameter of superior haemorrhoidal vein, and mesorectal vascular lesion (MVL) grade on rectal MRI (p<0.05) were associated with the possibility of metastasis for indeterminate hepatic lesions on CT. On multivariate analysis, MVL grade and MRF invasion on rectal MRI were independent factors associated with the possibility of metastasis for indeterminate hepatic lesions on CT (p<0.0005 and p=0.0066, respectively). CONCLUSION: MVL grade and MRF invasion on rectal MRI are independent factors for estimating hepatic metastasis among indeterminate hepatic lesions on CT in patients with rectal cancer.


Subject(s)
Liver Neoplasms/diagnostic imaging , Liver Neoplasms/secondary , Rectal Neoplasms/diagnostic imaging , Rectal Neoplasms/pathology , Tomography, X-Ray Computed , Adult , Aged , Aged, 80 and over , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Risk Assessment , Risk Factors
14.
Clin Radiol ; 72(2): 141-149, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27742104

ABSTRACT

AIM: To evaluate the efficacy of radiofrequency ablation (RFA) and transarterial chemoembolisation (TACE) as a first-line treatment for isolated intrahepatic recurrent hepatocellular carcinoma (IIR-HCC) after liver transplantation (LT). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board. Between January 2005 and January 2015, 588 consecutive patients underwent LT for the treatment of HCC. Among them, 27 patients with IIR-HCCs after LT who were treated with RFA (n=6) or TACE (n=21) as a first-line treatment were retrospectively included in this study. Disease-free and overall survival rates were estimated using the Kaplan-Meier method. Risk factors affecting these outcomes were assessed with Cox regression models. RESULTS: Except for the total number of recurrent tumours and time-to-tumour recurrence after LT, baseline characteristics were not significantly different between the groups. The 2-year disease-free survival rates for RFA and TACE (20% versus 14%, respectively; p=0.180) and 4-year overall survival rates (33% versus 25%, respectively; p=0.065) were not significantly different between groups. In addition, the types of treatment were not associated with disease-free or overall survival in multivariate analyses. CONCLUSION: TACE may be an effective treatment comparable to RFA in patients with IIR-HCC after LT when RFA is not feasible.


Subject(s)
Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/therapy , Catheter Ablation/mortality , Liver Neoplasms/mortality , Liver Neoplasms/therapy , Liver Transplantation/mortality , Neoplasm Recurrence, Local/mortality , Adult , Catheter Ablation/statistics & numerical data , Chemoembolization, Therapeutic/mortality , Chemoembolization, Therapeutic/statistics & numerical data , Combined Modality Therapy/mortality , Combined Modality Therapy/statistics & numerical data , Comorbidity , Female , Humans , Liver Transplantation/statistics & numerical data , Longitudinal Studies , Male , Middle Aged , Neoplasm Recurrence, Local/prevention & control , Prevalence , Republic of Korea/epidemiology , Retrospective Studies , Survival Rate , Treatment Outcome
15.
Sci Rep ; 6: 31345, 2016 08 24.
Article in English | MEDLINE | ID: mdl-27554285

ABSTRACT

The magnetic properties and electronic structures of pure, doped and defective cerium oxide (CeO2) have been studied theoretically by means of ab initio calculations based on the density function theory (DFT) with the hybrid HF/DFT technique named PBE0. Carbon (C), nitrogen (N), phosphorus (P), sulphur (S), lanthanum (La) and praseodymium (Pr) doped in CeO2 and CeO2 containing oxygen vacancies (Ov) were considered. Our spin-polarized calculations show that C, N, Pr dopants and Ov defects magnetize the non-magnetic CeO2 in different degree. The optical band gap related to photocatalysis for pure CeO2, corresponding to the ultraviolet region, is reduced obviously by C, N, S, Pr impurities and oxygen vacancies, shifting to the visible region and even further to the infrared range. Especially, N-, S- and Pr-doped CeO2 could be used to photocatalytic water splitting for hydrogen production. As the concentration of Ov increasing up to 5%, the CeO2 exhibits a half-metallic properties.

16.
J Nanosci Nanotechnol ; 16(2): 1592-5, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27433627

ABSTRACT

The thermal conductivity of a single ZnO nanowire with diameter of ~150 nm was measured using a four-point-probe 3omega method over a temperature range of 140-300 K. The measured ther- mal conductivity of ZnO nanowire is strongly reduced compared to bulk ZnO crystal due to the enhanced phonon-boundary and impurity (isotope) scattering. The maximum of the thermal conductivity is shifted to a higher temperature than that of bulk counterpart. Temperature dependent measurements show that beyond the low-temperature maximum, the thermal conductivity decreases with temperature as T(-1.5) indicating strong impurity (isotope) scattering at intermediate and high temperatures.

17.
Clin Radiol ; 71(4): 402.e9-402.e15, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26874658

ABSTRACT

AIM: To evaluate the conventional and diffusion-weighted magnetic resonance imaging (MRI) images of tumefactive gallbladder sludge. MATERIALS AND METHODS: The institutional review board approved this retrospective study. Between January 2006 and January 2015, 3478 patients were diagnosed with gallbladder sludge by ultrasonography (US). Of them, 12 patients (eight male, four female; mean age, 63.6 years) with 12 tumefactive gallbladder sludge lesions, who underwent subsequent MRI for further evaluation within 1 month, were included in this study. Data regarding the clinical features, presence of enhancement, and signal intensities of the T2-, T1-, and diffusion-weighted images were collected. RESULTS: All cases of tumefactive sludge were detected incidentally. None of the patients had any predisposing factors for biliary sludge. The tumefactive gallbladder sludge was predominantly seen as a well-defined mass-like lesion. It showed hyperintensity on T1-weighted images (91.7%, 11/12), and variable signal intensities on T2-weighted images. Most of the tumefactive sludge lesions showed no enhancement on the dynamic phases (90%, 9/10). There were no cases with diffusion restriction. Among the patients with follow-up US data (n=7), all the lesions were found to have either disappeared or decreased in size. CONCLUSION: Although tumefactive gallbladder sludge on US can mimic gallbladder cancer, its hyperintensity on a T1-weighted image, and the absence of enhancement and diffusion restriction on MRI images can be helpful for differentiating it from a tumorous condition.


Subject(s)
Bile , Gallbladder/anatomy & histology , Magnetic Resonance Imaging , Aged , Contrast Media , Diffusion Magnetic Resonance Imaging , Female , Gadolinium DTPA , Humans , Image Enhancement , Male , Middle Aged , Reproducibility of Results , Retrospective Studies
18.
Br J Radiol ; 88(1050): 20140497, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25882688

ABSTRACT

OBJECTIVE: To compare the performance of the 15-G internally cooled electrode with that of the conventional 17-G internally cooled electrode. METHODS: A total of 40 (20 for each electrode) and 20 ablation zones (10 for each electrode) were made in extracted bovine livers and in in vivo porcine livers, respectively. Technical parameters, three dimensions [long-axis diameter (Dl), vertical-axis diameter (Dv) and short-axis diameter (Ds)], volume and the circularity (Ds/Dl) of the ablation zone were compared. RESULTS: The total delivered energy was higher in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (8.78 ± 1.06 vs 7.70 ± 0.98 kcal, p = 0.033; 11.20 ± 1.13 vs 8.49 ± 0.35 kcal, p = 0.001, respectively). The three dimensions of the ablation zone had a tendency to be larger in the 15-G group than in the 17-G group in both studies. The ablation volume was larger in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (29.61 ± 7.10 vs 23.86 ± 3.82 cm(3), p = 0.015; 10.26 ± 2.28 vs 7.79 ± 1.68 cm(3), p = 0.028, respectively). The circularity of ablation zone was not significantly different in both the studies. CONCLUSION: The size of ablation zone was larger in the 15-G internally cooled electrode than in the 17-G electrode in both ex vivo and in vivo studies. ADVANCES IN KNOWLEDGE: Radiofrequency ablation of hepatic tumours using 15-G electrode is useful to create larger ablation zones.


Subject(s)
Catheter Ablation/instrumentation , Electrodes , Liver/surgery , Animals , Cattle , Equipment Design , In Vitro Techniques , Models, Animal , Radio Waves , Swine
19.
Clin Radiol ; 70(4): 387-94, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25582889

ABSTRACT

AIM: To evaluate the usefulness of fusion imaging with real-time ultrasonography (US) and three-dimensional (3D) US for the guidance of radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs) 2-5 cm in diameter. MATERIALS AND METHODS: This study was conducted as a retrospective cohort study. It was approved by the institutional review board and informed consent was waived. During percutaneous RFA of HCCs, targeting was performed under conventional fusion imaging guidance, whereas monitoring and controlling were conducted under fusion with 3D US guidance. Technical success, technique effectiveness, incidence of major complications, and local tumour progression rate were evaluated. According to tumour size (small: <3 cm versus medium: 3-5 cm), the roundness indexes of the ablation zones and local tumour progression rates were compared. RESULTS: There were 29 small-sized HCCs (2.5 ± 0.3 cm) and 17 medium-sized HCCs (3.4 ± 0.5 cm). All RFA procedures were performed in a single RFA session. Both the technical success and technique effectiveness rates were 100%. One patient with medium-sized HCC developed a hepatic abscess (n = 1) as a major complication. The local tumour progression rate was 8.7% (4/46) with a mean follow-up period of 18.2 months. The roundness indexes of the ablation zone were not significantly different between small- and medium-sized HCCs, and the local tumour progression rates were also not significantly different between the two groups [3.4% (1/29) versus 17.6% (3/17); p = 0.135]. CONCLUSION: Image fusion with real-time US and 3D US is useful for the guidance of percutaneous RFA for HCCs 2-5 cm in diameter.


Subject(s)
Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/surgery , Catheter Ablation/methods , Imaging, Three-Dimensional , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/pathology , Female , Humans , Liver Neoplasms/pathology , Male , Middle Aged , Retrospective Studies , Treatment Outcome , Ultrasonography
20.
Chemphyschem ; 16(3): 634-9, 2015 Feb 23.
Article in English | MEDLINE | ID: mdl-25425330

ABSTRACT

The decoration of a BC3 monolayer with the polylithiated molecules CLi4 and OLi2 has been extensively investigated to study the hydrogen-storage efficiency of the materials by first principles electronic structure calculations. The binding energies of both lithiated species with the BC3 substrate are much higher than their respective cohesive energies, which confirms the stability of the doped systems. A significant positive charge on the Li atom in each of the dopants facilitates the adsorption of multiple H2 molecules under the influence of electrostatic and van der Waals interactions. We observe a high H2 -storage capacity of 11.88 and 8.70 wt % for the BC3 -CLi4 and BC3 -OLi2 systems, respectively, making them promising candidates as efficient energy-storage systems.

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