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1.
Small Methods ; 5(9): e2100195, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34928059

ABSTRACT

Highly conductive 3D ordered mesoporous Ni7 S6 -MoS2 /N-doped graphitic carbon (NGC) composite (P-NiMoS/C) microspheres are prepared as anode materials for Na-ion batteries. The rationally designed nanostructure comprises stable Ni7 S6 - and MoS2 -phases along with the homogeneously distributed ordered mesopores (ϕ = 50 nm) over the external and internal structures generated through thermal decomposition of polystyrene nanobeads (ϕ = 100 nm). Therefore, the P-NiMoS/C microspheres deliver initial discharge capacities of 662, 419, 373, 300, 231, 181, and 146 mA h g-1 at current densities of 0.5, 1, 2, 4, 6, 8, and 10 A g-1 , respectively. Furthermore, P-NiMoS/C exhibits a stable discharge capacity of 444 mA h g-1 at the end of the 150th cycle at a current density of 0.5 A g-1 , indicating higher cycling stability than the filled, that is, non-mesoporous, Ni3 S2 -MoS2 /NGC (F-NiMoS/C) microspheres and filled carbon-free Ni3 S2 -MoS2 (F-NiMoS) microspheres. The superior electrochemical performance of P-NiMoS/C microspheres is attributed to the rapid Na+ ion diffusion, alleviation of severe volume stress during prolonged cycling, and higher electrical conductivity of NGC, which results in fast charge transfer during the redox processes. The results in the present study can provide fundamental knowledge for the development of multicomponent, porous, and highly conductive anodes for various applications.

2.
Adv Sci (Weinh) ; 7(17): 2001358, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32995129

ABSTRACT

Stretchable lithium batteries have attracted considerable attention as components in future electronic devices, such as wearable devices, sensors, and body-attachment healthcare devices. However, several challenges still exist in the bid to obtain excellent electrochemical properties for stretchable batteries. Here, a unique stretchable lithium full-cell battery is designed using 1D nanofiber active materials, stretchable gel polymer electrolyte, and wrinkle structure electrodes. A SnO2/C nanofiber anode and a LiFePO4/C nanofiber cathode introduce meso- and micropores for lithium-ion diffusion and electrolyte penetration. The stretchable full-cell consists of an elastic poly(dimethylsiloxane) (PDMS) wrapping film, SnO2/C and LiFePO4/C nanofiber electrodes with a wrinkle structure fixed on the PDMS wrapping film by an adhesive polymer, and a gel polymer electrolyte. The specific capacity of the stretchable full-battery is maintained at 128.3 mAh g-1 (capacity retention of 92%) even after a 30% strain, as compared with 136.8 mAh g-1 before strain. The energy densities are 458.8 Wh kg-1 in the released state and 423.4 Wh kg-1 in the stretched state (based on the electrode), respectively. The high capacity and stability in the stretched state demonstrate the potential of the stretchable battery to overcome its limitations.

3.
Data Brief ; 25: 104302, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31406910

ABSTRACT

The data presented in this article are related to the research article entitled "Hierarchical yolk-shell CNT-(NiCo)O_C microspheres prepared by one-pot spray pyrolysis as anodes in lithium-ion batteries" (Oh et al., 2019). The data presented in this manuscript showed the effect of the reaction temperature during spray pyrolysis on the obtained microspheres morphology. Each morphology and phase of the microspheres obtained after spray pyrolysis were investigated.

4.
Nanoscale ; 10(45): 21483-21491, 2018 Dec 07.
Article in English | MEDLINE | ID: mdl-30427034

ABSTRACT

Rattle-type porous Sn/carbon (Sn/C) composite fibers with uniformly distributed nanovoids containing metallic Sn nanoparticles in void space surrounded by C walls (denoted as RT-Sn@C porous fiber) were prepared by electrospinning and subsequent facile heat-treatment. Highly concentrated polystyrene nanobeads used as a sacrificial template played a key role in the synthesis of the unique structured RT-Sn@C porous fiber. The RT-Sn@C porous fiber exhibited excellent long-term cycling and rate performances. The discharge capacity of the RT-Sn@C porous fiber at the 1000th cycle was 675 mA h g-1 at a high current density of 3.0 A g-1. The RT-Sn@C porous fiber had final discharge capacities of 991, 924, 890, 848, 784, 717, 679, and 614 mA h g-1 at current densities of 0.1, 0.2, 0.3, 0.5, 1.0, 2.0, 3.0, 5.0, and 10.0 A g-1, respectively. The numerous void spaces, surrounding a Sn nanoparticle as the rattle-type particle, and the surrounding C could efficiently accommodate the volume changes of the Sn nanoparticles, improve the electrical conductivity, and enable efficient penetration of the liquid electrolyte into the structure.

5.
Nanoscale ; 10(39): 18734-18741, 2018 Oct 21.
Article in English | MEDLINE | ID: mdl-30270367

ABSTRACT

Among the various nanostructures, porous materials with controlled pore structures have been widely used for designing transition metal-based anode materials for lithium-ion batteries, because they provide good access to electrolyte and can effectively accommodate stress arising from volume changes. In particular, ternary transition metal oxide materials containing nanovoids, arranged with high degree of periodicity, are ideal for enhancing lithium-ion storage capability. In this study, we provide a method using spray pyrolysis for the synthesis of mesoporous multicomponent metal oxide microspheres containing Ni and Mo components and N-doped carbon, in which three-dimensionally ordered 40 nm-sized mesopores are interconnected. During the synthesis, polystyrene nanobeads are used as a sacrificial template and are readily eliminated via thermal decomposition. Increased concentrations of polystyrene nanobeads enables the formation of open channels throughout the microspheres. When employed as a lithium-ion battery anode, the mesoporous multicomponent metal oxide microspheres containing Ni and Mo components and N-doped carbon exhibit high reversible capacity, good cycling stability, and excellent rate performance. After 1000 cycles, the microspheres deliver a discharge capacity of 693 mA h g-1 at a current density of 1.0 A g-1.

6.
Clin Mol Hepatol ; 22(2): 272-5, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27209646

ABSTRACT

Iodine-131 is a radioisotope that is routinely used for the treatment of differentiated thyroid cancer after total or near-total thyroidectomy. However, there is some evidence that iodine-131 can induce liver injury . Here we report a rare case of drug-induced liver injury (DILI) caused by iodine-131 in a patient with regional lymph node metastasis after total thyroidectomy. A 47-year-old woman was admitted with elevated liver enzymes and symptoms of general weakness and nausea. Ten weeks earlier she had undergone a total thyroidectomy for papillary thyroid carcinoma and had subsequently been prescribed levothyroxine to reduce the level of thyroid-stimulating hormone. Eight weeks after surgery she underwent iodine-131 ablative therapy at a dose of 100 millicuries, and subsequently presented with acute hepatitis after 10 days. To rule out all possible causative factors, abdominal ultrasonography, endoscopic ultrasonography (on the biliary tree and gall bladder), and a liver biopsy were performed. DILI caused by iodine-131 was suspected. Oral prednisolone was started at 30 mg/day, to which the patient responded well.


Subject(s)
Chemical and Drug Induced Liver Injury/diagnosis , Abdomen/diagnostic imaging , Chemical and Drug Induced Liver Injury/drug therapy , Female , Humans , Iodine Radioisotopes/chemistry , Lymph Nodes/pathology , Lymphatic Metastasis , Middle Aged , Prednisolone/therapeutic use , Thyroid Neoplasms/drug therapy , Thyroid Neoplasms/surgery , Thyroidectomy , Thyroxine/therapeutic use , Ultrasonography
7.
J Bone Metab ; 22(3): 135-41, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26389089

ABSTRACT

Untreated hyperthyroidism and high-dose thyroid hormone are associated with osteoporosis, and increased bone mineral density (BMD) has been demonstrated in postmenopausal females with hypoparathyroidism. Studies on the effect of suppressive levothyroxine (LT4) therapy on BMD and bone metabolism after total thyroidectomy in patients with differentiated thyroid carcinoma have presented conflicting results, and few studies in relation to the status of hypoparathyroidism have been studied. One hundred postmenopausal women and 24 premenopausal women on LT4 suppression therapy were included in this study. BMD of lumbar spine and femur and bone turnover markers were measured at the baseline and during the follow-up period up to 18 months using dual energy X-ray absorptiometry. Biochemical marker of bone resorption was measured by urine deoxypyridinoline and bone formation by serum osteocalcin. The age ranged from 36 to 64 years old. Thyroid stimulating hormone (TSH) was suppressed during the study. The results showed that BMD of femur and lumbar spine were not significantly changed in both pre- and postmenopausal women except femur neck in postmenopausal women without hypoparathyroidism. Patients with hypoparathyroidism had higher BMD gain than those without hypoparathyroidism in total hip (1.25 vs. -1.18%, P=0.015). Biochemical markers of bone turnover, serum osteocalcin, and urine deoxypyridinoline did not show significant change. In conclusion, patients with well differentiated thyroid carcinoma are not at a great risk of bone loss after LT4 suppressive therapy. The state of hypoparathyroidism is associated with increased BMD, particularly in postmenopausal women.

8.
BMB Rep ; 48(1): 42-7, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24856826

ABSTRACT

Streptococcus mutans is frequently associated with dental caries. Bacterial fermentation of food debris generates an acidic environment on the tooth surface, ultimately resulting in tooth deterioration. Therefore, various mouthwashes have been used to reduce and prevent Streptococcus mutans. The aim of this study was to evaluate the antimicrobial activities of 4 commercial mouthwashes and those of 10% and 20% ethanol solutions (formula A, B, C, D, E and F) against Streptococcus mutans using biofilm and planktonic methods. The range of reduction in the viable cell count of Streptococcus mutans as estimated by the biofilm and planktonic methods was 0.05-5.51 log (P ≤ 0.01) and 1.23-7.51 log (P ≤ 0.001) compared with the negative control, respectively, indicating that the planktonic method had a stronger antibacterial effect against S. mutans. Among the tested formulations, formula A (Garglin regular® mouthwash) was the most effective against Streptococcus mutans (P ≤ 0.001).


Subject(s)
Anti-Infective Agents/pharmacology , Mouthwashes/pharmacology , Streptococcus mutans/physiology , Biofilms/drug effects , Microbial Sensitivity Tests , Republic of Korea , Streptococcus mutans/drug effects
9.
Org Lett ; 16(5): 1310-3, 2014 Mar 07.
Article in English | MEDLINE | ID: mdl-24571334

ABSTRACT

Photoredox-catalyzed vicinal chlorotrifluoromethylation of alkene is described. In the presence of Ru(Phen)3Cl2, CF3SO2Cl was used as a source for the CF3 radical and chloride ion under visible light irradiation. Various terminal and internal alkenes were transformed to their vicinal chlorotrifluoromethylated derivatives. Biologically active compounds were applied under the condition to obtain desired products, suggesting that the method could be feasible for late-stage modification in drug discovery.


Subject(s)
Alkenes/chemistry , Hydrocarbons, Halogenated/chemistry , Catalysis , Combinatorial Chemistry Techniques , Light , Molecular Structure , Photochemical Processes
10.
J Microbiol ; 51(5): 671-5, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24037661

ABSTRACT

Norovirus, Rotavirus group A, the Hepatitis A virus, and Coxsackievirus are all common causes of gastroenteritis. Conventional diagnoses of these causative agents are based on antigen detection and electron microscopy. To improve the diagnostic potential for viral gastroenteritis, internally controlled multiplex real-time polymerase chain reaction (PCR) methods have been recently developed. In this study, individual real-time PCRs were developed and optimized for specific detections of Norovirus genogroup I, Norovirus genogroup II, Rotavirus group A, the Hepatitis A virus, and Coxsackievirus group B1. Subsequently, individual PCRs were combined with multiplex PCR reactions. In general, multiplex real-time PCR assays showed comparable sensitivities and specificities with individual assays. A retrospective clinical evaluation showed increased pathogen detection in 29% of samples using conventional PCR methods. Prospective clinical evaluations were detected in 123 of the 227 (54%) total samples used in the multiplex real-time PCR analysis. The Norovirus genogroup II was found most frequently (23%), followed by Rotavirus (20%), the Hepatitis A virus (4.5%), Coxsackievirus (3.5%), and Norovirus genogroup I (2.6%). Internally controlled multiplex real-time PCR assays for the simultaneous detection of Rotavirus, Coxsackievirus group B, the Hepatitis A virus, and Norovirus genogroups I and II showed significant improvement in the diagnosis of viral gastroenteritis.


Subject(s)
Foodborne Diseases/diagnosis , Gastroenteritis/diagnosis , Multiplex Polymerase Chain Reaction/methods , RNA Viruses/isolation & purification , Real-Time Polymerase Chain Reaction/methods , Virology/methods , Water Microbiology , Foodborne Diseases/virology , Gastroenteritis/virology , RNA Viruses/genetics , Sensitivity and Specificity
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