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71.
Jeonggeun Jo Sukyeung Nam Seungmi Han Vinod Mathew Muhammad Hilmy Alfaruqi Duong Tung Pham Seokhun Kim Sohyun Park Sunhyun Park Jaekook Kim 《RSC advances》2019,9(42):24030
A simple one-pot polyol-assisted pyro-technique has been adopted to synthesize highly crystalline, carbon-coated LiMn2O4 (LMO/C) nanoparticles for use as a cathode material in rechargeable Li-ion battery (LIB) applications. The phase purity, structure and stoichiometry of the prepared cathode was confirmed using X-ray techniques that included high-resolution powder X-ray diffraction and X-ray absorption fine structure spectroscopy. Electron microscopy studies established that the synthetic technique facilitated the production of nano-sized LMO particles with uniform carbon coating. The prepared LMO/C cathode demonstrates excellent electrochemical properties (cycling stabilities of 86% and 77.5% and high rate capabilities of 79% and 36% within the potential windows of 3.3–4.3 V and 2.5–4.3 V, respectively). The high electrochemical performance of the LMO/C cathode is attributed to the nano-size of the LiMn2O4 particles enabling high surface area and hence greater lithium insertion and also the uniform amorphous carbon coating facilitating effective reduction in manganese dissolution and volume expansion during the lithium de-intercalation/intercalation reactions. In addition, cyclic voltametry and impedance characterization confirm the reversible Li-intercalation and the role of the solid electrolyte interface layer (SEI) in the stable electrochemical reaction of the LMO/C electrode. Furthermore, this study shows the efficacy of a simple and low-cost pyro-synthetic method to realize high performance nano-sized particle electrodes with uniform carbon coating for useful energy storage applications.A simple one-pot polyol-assisted pyro-synthesized LiMn2O4/C cathode demonstrated remarkable lithium cycling stabilities of 86% and 19% and high rate capabilities of 77.5% and 36% at 3.3–4.3 V and 2.5–4.3V, respectively. 相似文献
72.
Introduction and hypothesis
To evaluate lower urinary tract injuries in women with ≥2 prior cesarean deliveries (CD) undergoing benign hysterectomies.Methods
This is a planned secondary analysis of all hysterectomies performed from 2000 to 2009 at Grady Memorial Hospital. Demographic, operative and postoperative data were reviewed. Women undergoing benign hysterectomies with ≥2 CD were compared with women with no prior CD. Categorical variables were analyzed using Chi-squared or Fisher’s exact test, while Student’s t test was used for continuous variables. Logistic regression was used for multivariate analysis.Results
2,214 women met the inclusion criteria (284 with ≥2 CD, 1,930 with no CD). The proportion of women having vaginal hysterectomy, abdominal hysterectomy, and laparoscopically assisted vaginal hysterectomy were 38 %, 53 %, and 9 % respectively. Women with multiple CD had greater blood loss and longer operative times. They also required more transfusions (23 % vs 15 %, P?=?0.001) and developed more abdominal wounds (6 % vs 3 %, P?=?0.002) or urinary infections (6 % vs 3 %, P?=?0.03). Women with ≥2 CD were at greater risk of incidental cystotomies (OR: 8.55, 95 % CI: 3.98–18.36).Conclusions
Multiple prior cesarean deliveries increase a woman’s risk of cystotomy during hysterectomy. They also require more transfusions and develop more urinary or abdominal wound infections. 相似文献73.
74.
75.
Nguyen My Nuong Nguyen Thuy Vy Ho-Huynh Thuy Duong 《African journal of traditional, complementary, and alternative medicines》2014,11(4):136-141
Background
Traditional formulae usually exhibit therapeutic effects through the combinations of different ingredients. The purpose of this study was to investigate in vitro anti-oxidative activity of Thanh Hao Miet Giap Thang (THMGT) (Sweet Wormwood and Tortoise Shell Decoction) formula and the interactions of its ingredients leading to the overall anti-oxidative effect.Materials and Methods
We prepared 31 combinations containing two to four of the five ingredients including Herba Artemisia apiacea L (HbA), Carapax Trionycis (Tryonix sinensis) (CT), Rhizoma Anemarrhenae (Anemarrhena asphodeloides) (RzA), Radix Rehmanniae (Rehmannia glutinosa Libosch) (RdR), Moutan Cortex (Paeonia suffruticosa) (MC). These combinations were tested for anti-oxidative activity using DCFH-DA and DPPH assays on Hep G2 cells. We also analyzed changes in expression of genes involved in antioxidant defense system including Nuclear Factor Erythroid-Derived 2-Like 2 (NFE2L2), catalase (CAT), heme oxygenase-1 (HO-1), glutathione peroxidase (GPx), cytoplasmic superoxide dismutase (SOD1), mitochondrial superoxide dismutase (SOD2).Results
The complete formula and all combinations containing Moutan Cortex showed high antioxidant activity in both radical solution-based chemical assay and cellular-based assay. On the contrary, Carapax Trionycis displayed inhibitory effect on the overall antioxidant activity when present in a combination, an effect clearly emphasized in cellular-based assay. Hep G2 cells treated with the formula showed increased gene expression of HO-1 and SOD2 while expression of CAT, SOD1, GPx was unchanged.Conclusion
Our results suggested that THMGT had anti-oxidative activity essentially through intrinsic reducing capacities and the overall activity of the formula resulted from enhancing and inhibiting interactions of ingredients. 相似文献76.
Frequent coexistence of RAS mutations in RUNX1‐mutated acute myeloid leukemia in Arab Asian children
Lika'a Fasih Y. Al‐Kzayer MD PhD Kazuo Sakashita MD PhD Mazin Faisal Al‐Jadiry MD Salma Abbas Al‐Hadad MD Le T.N. Uyen MD Tingting Liu MD Kazuyuki Matsuda PhD Jaafar M.H. Abdulkadhim MD Tariq Abadi Al‐Shujairi MD Zead Ismael I.K. Matti MD Janan Ghalib Hasan MD Hussam M. Salih Al‐Abdullah MD Toshi Inoshita MD Minoru Kamata MD Maher A. Sughayer MD Faris F. Madanat MD Kenichi Koike MD PhD 《Pediatric blood & cancer》2014,61(11):1980-1985
77.
Thi Le Anh Nguyen Thi Hoai Nam Doan Dinh Hieu Truong Nguyen Thi Ai Nhung Duong Tuan Quang Dorra Khiri Sonia Taamalli Florent Louis Abderrahman El Bakali Duy Quang Dao 《RSC advances》2021,11(35):21433
Antioxidant and UV absorption activities of three aaptamine derivatives including piperidine[3,2-b]demethyl(oxy)aaptamine (C1), 9-amino-2-ethoxy-8-methoxy-3H-benzo[de][1,6]naphthyridine-3-one (C2), and 2-(sec-butyl)-7,8-dimethoxybenzo[de]imidazo[4,5,1-ij][1,6]-naphthyridin-10(9H)-one (C3) were theoretically studied by density functional theory (DFT). Direct antioxidant activities of C1–C3 were firstly evaluated via their intrinsic thermochemical properties and the radical scavenging activity of the potential antioxidants with the HOO˙/HO˙ radicals via four mechanisms, including: hydrogen atom transfer (HAT), single electron transfer (SET), proton loss (PL) and radical adduct formation (RAF). Kinetic calculation reveals that HOO˙ scavenging in water occurs via HAT mechanism with C1 (kapp, 7.13 × 106 M−1 s−1) while RAF is more dominant with C2 (kapp, 1.40 × 105 M−1 s−1) and C3 (kapp, 2.90 × 105 M−1 s−1). Antioxidant activity of aaptamine derivatives can be classified as C1 > C3 > C2. Indirect antioxidant properties based on Cu(i) and Cu(ii) ions chelating activity were also investigated in aqueous phase. All three studied compounds show spontaneous and favorable Cu(i) ion chelating activity with ΔG0 being −15.4, −13.7, and −15.7 kcal mol−1, whereas ΔG0 for Cu(ii) chelation are −10.4, −10.8, and −2.2 kcal mol−1 for C1, C2 and C3, respectively. In addition, all compounds show UVA and UVB absorption; in which the excitations are determined mostly as π–π* transition. Overall, the results suggest the potential applications of the aaptamines in pharmaceutics and cosmetics, i.e. as a sunscreen and antioxidant ingredient.Antioxidant and UV absorption activities of three aaptamine derivatives were theoretically studied by density functional theory (DFT) and time-dependent density functional theory (TD-DFT). 相似文献
78.
79.
Ngo Tuan Cuong Nguyen Thi Mai Nguyen Thanh Tung Ngo Thi Lan Long Van Duong Minh Tho Nguyen Nguyen Minh Tam 《RSC advances》2021,11(63):40072
Geometrical and electronic structures of the 13-atom clusters AlxScy with x + y = 13, as well as their thermodynamic stabilities were investigated using DFT calculations. Both anionic and neutral isomers of AlxScy were found to retain an icosahedral shape of both Al13 and Sc13 systems in which an Al atom occupies the endohedral central position of the icosahedral cage, irrespective of the number of Al atoms present. Such a phenomenon occurs to maximize the number of stronger Al–Al and Sc–Al bonds instead of the weaker Sc–Sc bonds. NBO analyses were applied to examine their electron configurations and rationalize the large number of open shells and thereby high multiplicities of the mixed clusters having more than three Sc atoms. The SOMOs are the molecular orbitals belonged to the irreducible representations of the symmetry point group of the clusters studied, rather than to the cluster electron shells. Evaluation of the average binding energies showed that the thermodynamic stability of AlxScy clusters is insignificantly altered as the number y goes from 0 to 7 and then steadily decreases when y attains the 7–13 range. Increase of the Sc atom number also reduces the electron affinities of the binary AlxScy clusters, and thus they gradually lose the superhalogen characteristics with respect to the pure Al13.The icosahedral structure of the AlxScy clusters with x + y = 13. 相似文献
80.
The floods in the Vietnamese Mekong Delta have long caused a shortage of clean water supply, which has a significant impact on the indigenous people in the region. We have conducted a preliminary survey of the water quality of the Hau Giang River (one of the two main branches of the Mekong River) before, during, and after the flood season. The obtained results demonstrated that the water in the Hau Giang River was highly turbid and contaminated with a large number of harmful microorganisms. Thus, in this study, a simple filter system based on silver nanoparticles coated onto activated carbon derived from rice husk (AgNPs@AC) has been proposed for treating floodwater from the Hau Giang River. The optimal conditions for AgNPs@AC preparation were established. The prepared AgNPs@AC was then characterized using various surface analyses such as SEM, TEM, XRD, BET, FTIR, and DLS. The initial floodwater source would be pre-treated with polyaluminum chloride using the coagulation–sedimentation method to remove the suspended solids before being discharged into the filtration column containing AgNPs@AC. The results showed that the filter system based on AgNPs@AC performed well in removing turbidity, dissolved solids, suspended solids, color, and bacteria from the floodwater. In addition, it was determined that the filter column with a 30 mm thick AgNPs@AC layer could continuously process 1300 m3 of the floodwater and had a service life of more than two months. The findings of this study not only added to our understanding of the floodwater treatment capacity of activated carbon coated nanoparticles, but they also provided valuable information for water treatment plants along the Hau Giang River, aquatic ecosystem researchers, and public health researchers.In this study, a simple filter system based on silver nanoparticles coated onto activated carbon derived from rice husk (AgNPs@AC) has been proposed for treating floodwater from the Hau Giang River. 相似文献