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21.
Balal Yousaf Guijian Liu Qumber Abbas Ruwei Wang Habib Ullah Md Manik Mian Amina Audil Rashid 《RSC advances》2018,8(46):25983
Recently, nanosized metal-oxides have been extensively investigated for their ability to remove metal ions from aqueous media. However, the activity and capacity of these nanosized metal-oxides for removing metal ions decrease owing to their agglomeration in aqueous media. Herein, we synthesized a highly stable and magnetically separable rosin-biochar-coated (RBC) TiO2@C nanocomposite through a facile and environment-friendly wet chemical coating process, followed by a one-step heating route (pyrolysis) for efficient removal of Cr(vi) from aqueous solution. An array of techniques, namely, TEM, HRTEM, TEM-EDS, XRD, FTIR, VSM, BET and TGA, were used to characterize the prepared nanocomposite. The pyrolysis of rosin into biochar and the fabrication of Fe onto the RBC-TiO2@C nanocomposite were confirmed by FTIR and XRD examination, respectively. Moreover, TEM and HRTEM images and elemental mapping using TEM-EDS showed good dispersion of iron and carbon on the surface of the RBC-TiO2@C nanocomposite. Sorption of Cr(vi) ions on the surface of the RBC-TiO2@C nanocomposite was very fast and efficient, having a removal efficiency of ∼95% within the 1st minute of reaction. Furthermore, thermodynamic analysis showed negative values of Gibb''s free energy at all five temperatures, indicating that the adsorption of Cr(vi) ions on the RBC-TiO2@C nanocomposite was favorable and spontaneous. Conclusively, our results indicate that the RBC-TiO2@C nanocomposite can be used for efficient removal of Cr(vi) from aqueous media due to its novel synthesis and extraordinary adsorption efficacy during a short time period.A biochar-coated RBC-TiO2@C nanocomposite was synthesized using a wet chemical coating followed by a one-step heating route (pyrolysis) for the efficient removal of Cr(vi). 相似文献
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Great ‘app‐eal’ but not there yet: A review of iPhone nutrition applications relevant to child weight management
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24.
Abdallah F. Zedan Assem T. Mohamed M. Samy El-Shall Siham Y. AlQaradawi Amina S. AlJaber 《RSC advances》2018,8(35):19499
Copper oxide (CuO) nanoparticles have received considerable interest as active and inexpensive catalysts for various gas–solid reactions. The CuO reducibility and surface reactivity are of crucial importance for the high catalytic activity. Herein, we demonstrate that the reducibility and stability of CuO nanoparticles can be controlled and tailored for the high catalytic activity of CO oxidation. The synthesized CuO nanoparticles possessed enhanced reducibility in CO atmosphere at lower reduction temperature of 126 °C compared to 284 °C for that of reference CuO particles. Moreover, the CuO catalysts with tailored reducibility demonstrated a reaction rate of 35 μmol s−1 g−1 and an apparent activation energy of 75 kJ mol−1. Furthermore, the tailored catalysts exhibited excellent long-term stability for CO oxidation for up to 48 h on stream. These readily-reducible CuO nanoparticles could serve as efficient, inexpensive and durable catalysts for CO oxidation at low temperatures.Copper oxide (CuO) nanoparticles of tailored reducibility could be used as inexpensive, efficient and durable catalysts for CO oxidation at low temperature. 相似文献
25.
Nathan J Kolla Brittany Matthews Alan A Wilson Sylvain Houle R Michael Bagby Paul Links Alexander I Simpson Amina Hussain Jeffrey H Meyer 《Neuropsychopharmacology》2015,40(11):2596-2603
Antisocial personality disorder (ASPD) often presents with highly impulsive, violent behavior, and pathological changes in the orbitofrontal cortex (OFC) and ventral striatum (VS) are implicated. Several compelling reasons support a relationship between low monoamine oxidase-A (MAO-A), an enzyme that regulates neurotransmitters, and ASPD. These include MAO-A knockout models in rodents evidencing impulsive aggression and positron emission tomography (PET) studies of healthy subjects reporting associations between low brain MAO-A levels and greater impulsivity or aggression. However, a fundamental gap in the literature is that it is unknown whether brain MAO-A levels are low in more severe, clinical disorders of impulsivity, such as ASPD. To address this issue, we applied [11C] harmine PET to measure MAO-A total distribution volume (MAO-A VT), an index of MAO-A density, in 18 male ASPD participants and 18 age- and sex-matched controls. OFC and VS MAO-A VT were lower in ASPD compared with controls (multivariate analysis of variance (MANOVA): F2,33=6.8, P=0.003; OFC and VS MAO-A VT each lower by 19%). Similar effects were observed in other brain regions: prefrontal cortex, anterior cingulate cortex, dorsal putamen, thalamus, hippocampus, and midbrain (MANOVA: F7,28=2.7, P=0.029). In ASPD, VS MAO-A VT was consistently negatively correlated with self-report and behavioral measures of impulsivity (r=−0.50 to −0.52, all P-values<0.05). This study is the first to demonstrate lower brain MAO-A levels in ASPD. Our results support an important extension of preclinical models of impulsive aggression into a human disorder marked by pathological aggression and impulsivity. 相似文献
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Osteogenesis imperfecta (OI) is a relatively common genetic skeletal disorder with an estimated frequency of 1 in 20 000 worldwide. The manifestations are diverse and although individually rare, the several different forms contribute to the production of a significant number of affected individuals with considerable morbidity and mortality. During the last decade, there have been extensive molecular investigations into the etiology of OI and these advances have direct relevance to the medical management of the disorder, and the purpose of this review is to document the history and evolution of the nosology of OI. The current nosology, based on molecular concepts, which are crucial in the identification of genotype‐phenotype correlations in persons with OI, is also outlined. The successive revisions of the nosology and classification of OI have highlighted the importance of the nomenclature of the condition in order for it to be recognized by clinicians, scientists and patient advocacy groups. In this way, improved counseling of patients and individualized, tailored therapeutic approaches based on the underlying pathophysiology of the individual's type of OI have been facilitated. 相似文献
28.
Tumor-resident adenosine-producing mesenchymal stem cells as a potential target for cancer treatment
Arab Samaneh Alizadeh Akram Asgharzade Samira 《Clinical and experimental medicine》2021,21(2):205-213
Clinical and Experimental Medicine - The development of new therapies based on tumor biology is one of the main topics in cancer treatment. In this regard, investigating the... 相似文献
29.
Amina Awad Hussien Shaker Wael Shendy Manal Fahmy 《Journal of Physical Therapy Science》2015,27(7):2195-2200
[Purpose] This study investigated the effect of shoulder girdle strengthening,
particularly the scapular muscles, on poststroke trunk alignment. [Subjects and Methods]
The study involved 30 patients with residual hemiparesis following cerebrovascular stroke.
Patient assessment included measuring shoulder muscle peak torque, scapular muscles peak
force, spinal lateral deviation angle, and motor functional performance. Patients were
randomly allocated either to the control group or the study group and received an
18-session strengthening program including active resisted exercises for shoulder
abductors and external rotators in addition to trunk control exercises. The study group
received additional strengthening exercises for the scapular muscles. [Results] The two
groups showed significant improvement in strength of all shoulder and scapular muscles,
with higher improvement in the study group. Similarly, the lateral spinal deviation angles
significantly improved in both groups, with significantly higher improvement in the study
group. Transfer activity, sitting balance, upper limb functions, and hand movements
significantly improved in the two groups, with higher improvement in the latter two
functions in the study group. [Conclusion] Strengthening of shoulder girdle muscles,
particularly scapular muscles, can significantly contribute to improving the postural
alignment of the trunk in patients with poststroke hemiparesis.Key words: Stroke, Scapular muscles strengthening, Lateral trunk alignment 相似文献
30.
Memon A Bartlett J Rose R Gray C 《The journals of gerontology. Series B, Psychological sciences and social sciences》2003,58(6):P338-P345
As a way to examine the nature of age-related differences in lineup identification accuracy, young (16-33 years) and older (60-82 years) witnesses viewed two similar videotaped incidents, one involving a young perpetrator and the other involving an older perpetrator. The incidents were followed by two separate lineups, one for the younger perpetrator and one for the older perpetrator. When the test delay was short (35 min), the young and older witnesses performed similarly on the lineups, but when the tests were delayed by 1 week, the older witnesses were substantially less accurate. When the target was absent from the lineups, the older witnesses made more false alarm errors, particularly when the faces were young. When the target was present in the lineups, correct identifications by both young and older witnesses were positively correlated with a measure of source recollection derived from a separate face-recognition task. Older witnesses scored poorly on this measure, suggesting that source-recollection deficits are partially responsible for age-related differences in performance on the lineup task. 相似文献