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991.
992.
Parmanand Ayushi Mittal Abhishek K. Singh Aarti Katharina Achazi Chuanxiong Nie Rainer Haag Sunil K. Sharma 《RSC advances》2020,10(61):37555
A new class of non-ionic amphiphiles is synthesized using a diaryl derivative of diglycerol as a central core and functionalizing it with long alkyl chains (C-12/C-15) and monomethoxy PEG moiety (Mn: 350/550) by following a chemo-enzymatic approach. The aggregation behavior of the amphiphiles in aqueous medium is studied by using dynamic light scattering (DLS) and fluorescence spectroscopy, whereas the size and morphology of the aggregates are studied by transmission electron microscopy (TEM). A hydrophobic dye, Nile red and a hydrophobic drug, nimodipine, are used to demonstrate the nano-carrier capability of these non-ionic amphiphilic systems and the results are compared with amphiphilic analogues obtained from the triaryl derivatives of triglycerol. The in vitro controlled release of the encapsulated dye is successfully carried out in the presence of immobilized Candida antarctica lipase (Novozym 435). Furthermore, cytotoxicity data is also collected which suggests that the amphiphiles are suitable for biomedical applications.A new series of oligo-glycerol based amphiphiles have been synthesized for drug delivery. 相似文献
993.
Petri M. Leukkunen Ekta Rani Assa Aravindh Sasikala Devi Harishchandra Singh Graham King Matti Alatalo Wei Cao Marko Huttula 《RSC advances》2020,10(60):36930
P25 comprising of mixed anatase and rutile phases is known to be highly photocatalytically active compared to the individual phases. Using a facile wet chemical method, we demonstrate a ternary nanocomposite consisting of Ni and Ag nanoparticles, decorated on the surface of XTiO2 (X: P25, rutile (R)) as an efficient visible-light-driven photocatalyst. Contrary to the current perspective, RTiO2-based Ni–Ag–RTiO2 shows the highest activity with the H2 evolution rate of ∼86 μmol g−1 W−1 h−1@535 nm. Together with quantitative assessment of active Ni, Ag and XTiO2 in these ternary systems using high energy synchrotron X-ray diffraction, transmission electron microscopy coupled energy dispersive spectroscopy mapping evidences the metal to semiconductor contact via Ag. The robust photocatalytic activity is attributed to the improved visible light absorption, as noted by the observed band edge of ∼2.67 eV corroborating well with the occurrence of Ti3+ in Ti 2p XPS. The effective charge separation due to intimate contact between Ni and RTiO2via Ag is further evidenced by the plasmon loss peak in Ag 3d XPS. Moreover, density functional theory calculations revealed enhanced adsorption of H2 on Ti8O16 clusters when both Ag and Ni are simultaneously present, owing to the hybridization of the metal atoms with d orbitals of Ti and p orbitals of O leading to enhanced bonding characteristics, as substantiated by the density of states. Additionally, the variation in the electronegativity in Bader charge analysis indicates the possibility of hydrogen evolution at the Ni sites, in agreement with the experimental observations.Robust photocatalytic activity of Ni–Ag–RTiO2 is attributed to the improved visible light absorption and effective charge separation due to intimate contact between Ni and RTiO2via Ag, as evidenced by Ti3+ in Ti 2p XPS and energy dispersive mapping. 相似文献
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997.
Person‐related determinants of TV viewing and computer time in a cohort of young Dutch adults: Who sits the most?
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![点击此处可从《Scandinavian journal of medicine & science in sports》网站下载免费的PDF全文](/ch/ext_images/free.gif)
L. Uijtdewilligen A. S. Singh M. J. M. Chinapaw J. W. R. Twisk W. van Mechelen 《Scandinavian journal of medicine & science in sports》2015,25(5):716-723
We aimed to assess the associations of person‐related factors with leisure time television (TV) viewing and computer time among young adults. We analyzed self‐reported TV viewing (h/week) and leisure computer time (h/week) from 475 Dutch young adults (47% male) who had participated in the Amsterdam Growth and Health Longitudinal Study at the age of 32 and 36 years. Sociodemographic factors (i.e., marital and employment status), physical factors (i.e., skin folds, aerobic fitness, neuromotor fitness, back problems), psychological factors (i.e., problem‐ and emotion‐focused coping, personality), lifestyle (i.e., alcohol consumption, smoking, energy intake, physical activity), and self‐rated health (i.e., general health status, mild health complaints) were assessed. Univariable and multivariable generalized estimating equations were performed. Male gender, higher sum of skin folds, lower values of aerobic fitness, higher rigidity, higher self‐sufficiency/recalcitrance, and smoking were positively associated with TV time. Male gender, higher sum of skin folds, higher scores on self‐esteem, low energy intake, and a not so good general health status were significantly associated with higher computer time. Determinants of TV viewing and computer time were not identical, suggesting that both behaviors (a) have different at‐risk populations and (b) should be targeted differently. 相似文献
998.
Intertechnique agreement and interstudy reproducibility of strain and diastolic strain rate at 1.5 and 3 tesla: A comparison of feature‐tracking and tagging in patients with aortic stenosis
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![点击此处可从《Journal of magnetic resonance imaging : JMRI》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Anvesha Singh MBChB Christopher D. Steadman MBChB MD Jamal N. Khan MBChB BMedSci Mark A. Horsfield PhD Soliana Bekele BSc Sheraz A. Nazir MBChB Prathap Kanagala MBChB Nicholas G.D. Masca MSc Patrick Clarysse PhD Gerry P. McCann MBChB MD 《Journal of magnetic resonance imaging : JMRI》2015,41(4):1129-1137
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Crescent fractures of the pelvis are usually described as posterior sacro iliac fracture dislocations. Rarely anterior displacement of the fractured iliac fragment along with dislocation has been reported in crescent fractures. Four cases of anterior fracture dislocation of the sacro iliac joint managed in the last two years by a single surgeon are presented. The injury mechanism, radiological diagnosis, management protocol along with functional outcomes of all the four patients have been discussed. CT scan is essential in the diagnosis and preoperative planning of this injury pattern. Early fixation along with proper reduction leads to excellent functional outcome in this subset of lateral compression injuries of the pelvis. 相似文献