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991.
Nafees Iqbal Syed Abid Ali Iqra Munir Saima Khan Khurshid Ayub Mariya al-Rashida Muhammad Islam Zahid Shafiq Ralf Ludwig Abdul Hameed 《RSC advances》2020,10(7):3992
Correction for ‘Acridinedione as selective flouride ion chemosensor: a detailed spectroscopic and quantum mechanical investigation’ by Nafees Iqbal et al., RSC Adv., 2018, 8, 1993–2003.The authors regret that the interpretation of the fluorescence spectra of compound 7i published in the original article was incorrect. In the original article, it was reported that upon excitation at 380 nm, the fluorescence spectrum of compound 7i showed two emission bands at 450 nm and 770 nm (Fig. 5b of the original article). The signal at 770 nm (previously reported as an emission band), is instead a second order diffraction (an artefact of diffraction grating/spectrofluorometer monochromator), as revealed from the literature.1,2 The authors thank a reader for highlighting this mistake.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
992.
To verify the possibility that the pedunculopontine nucleus is a source of glutamatergic terminals in contact with midbrain dopaminergic neurons in the squirrel monkey, we used the anterograde transport of Phaseolus vulgaris-leucoagglutinin in combination with preembedding immunohistochemistry for tyrosine hydroxylase and for calbindin D-28k and postembedding immunocytochemistry for glutamate and for γ-aminobutyric acid. Following tracer injections in the pedunculopontine nucleus, numerous anterogradely labeled fibers emerged from the injection sites to innervate densely the pars compacta of the substantia nigra and ventral tegmental area. The major type of labeled fibers were thin with multiple collaterals and varicosities that established intimate contacts with midbrain dopaminergic neurons. At the electron microscopic level, the anterogradely labeled boutons were medium sized (maximum diameter between 0.9 μm and 2.5 μm) and contained numerous round vesicles and mitochondria. Postembedding immunocytochemistry revealed that 40–60% of anterogradely labeled terminals were enriched in glutamate and formed asymmetric synapses with dendritic shafts of substantia nigra and ventral tegmental area neurons. In triple-immunostained sections, some of the postsynaptic targets to these terminals were found to be dopaminergic. In addition, 30–40% of the anterogradely labeled terminals in both regions displayed immunoreactivity for γ-aminobutyric acid and, in some cases, formed symmetric synapses with dendritic shafts. In conclusion, our results provide the first ultrastructural evidence for the existence of synaptic contacts between glutamate-enriched terminals from the pedunculopontine nucleus and midbrain dopaminergic neurons in primates. Our results also show that the pedunculopontine nucleus is a potential source of γ-aminobutyric acid input to this region. These findings suggest that the pedunculopontine nucleus may play an important role in the modulation of the activity of midbrain dopaminergic cells by releasing glutamate or γ-aminobutyric acid as neurotransmitter. © 1996 Wiley-Liss, Inc. 相似文献
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994.
Jane Tiller Ulrike Schmidt Shireen Ali Janet Treasure 《The International journal of eating disorders》1995,17(4):365-371
The level and direction of hostility in patients with bulimia nervosa, anorexia nervosa and a comparison group were measured using the Hostility and Direction of Hostility Questionnaire. A semistructured interview developed by Harris, Brown, and Bifulco (Psychological Medicine, 16, 641-659, 1986) was used to assess childhood care to examine whether a link exists between childhood exposure to aggression or parental neglect and adult hostility. Patients with eating disorders had significantly higher hostility levels and were significantly more intropunitive than the comparison group. Patients with bulimia nervosa were significantly more intropunitive than the comparison group. Patients with bulimia nervosa were significantly more hostile than patients with anorexia nervosa. Anorexia nervosa patients were more likely to direct hostility inwardly, rather than outwardly, when compared with bulimia nervosa patients. Impulsivity was associated with extrapunitiveness whereas intropunitiveness was associated with depression. Although some measures of poor childhood care correlated with adult hostility levels no clear pattern emerged. © 1995 by John Wiley & Sons, Inc. 相似文献
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998.
Mehrnoosh Tavakoli Ali Ghasemian Mohammad Reza Dehghani-Firouzabadi Bartomiej Mazela 《Materials》2022,15(1)
The inevitable destructive effects of moisture and temperature are obvious in cellulosic and nanocellulosic substrates. These materials are the main foundations of interdependent industries that produce products such as currency notes or high-quality packaging for sanitary, cosmetics, or ammunition in the defense industry. Therefore, it is essential to develop procedures to eliminate problems arising from humidity and fire to improve the quality of these green and sustainable materials. The production of waterproof and flame-resistant cellulose-based substrates has drawn increasing attention to resolve these drawbacks. In this review paper, we have initially summarized the most accessible cellulosic substrates, different kinds of nanocellulose, and the general information about water repellents and intumescent fireproof surfaces. Then, the potential and necessity of using cellulosic biobased substrates are addressed for use in modified shapes as waterproof and fire inhibitor coatings. Cost-effective, eco-friendly, and durable, dual-function coatings are also introduced as future challenges, which are exploited as water-repellents and flame-retardant cellulose-based surfaces for pulp and paper applications. 相似文献
999.
Mohsin Ali Khan Furqan Farooq Mohammad Faisal Javed Adeel Zafar Krzysztof Adam Ostrowski Fahid Aslam Seweryn Malazdrewicz Mariusz Malak 《Materials》2022,15(1)
To avoid time-consuming, costly, and laborious experimental tests that require skilled personnel, an effort has been made to formulate the depth of wear of fly-ash concrete using a comparative study of machine learning techniques, namely random forest regression (RFR) and gene expression programming (GEP). A widespread database comprising 216 experimental records was constructed from available research. The database includes depth of wear as a response parameter and nine different explanatory variables, i.e., cement content, fly ash, water content, fine and coarse aggregate, plasticizer, air-entraining agent, age of concrete, and time of testing. The performance of the models was judged via statistical metrics. The GEP model gives better performance with R2 and ρ equals 0.9667 and 0.0501 respectively and meet with the external validation criterion suggested in the previous literature. The k-fold cross-validation also verifies the accurateness of the model by evaluating R2, RSE, MAE, and RMSE. The sensitivity analysis of GEP equation indicated that the time of testing is the influential parameter. The results of this research can help the designers, practitioners, and researchers to quickly estimate the depth of wear of fly-ash concrete thus shortening its ecological susceptibilities that push to sustainable and faster construction from the viewpoint of environmentally friendly waste management. 相似文献
1000.
Patrizia Lamberti Monica La Mura Vincenzo Tucci Erick Nkyalu Ali Khan Marina Yakovleva Nadzeya Valynets Alesia Paddubskaya Aleksandr Saushin Viatcheslav Vanyukov Marian Baah Andrzej Urbanowicz Yuri Svirko Polina Kuzhir 《Materials》2022,15(3)
We report the performance of a graphene-enhanced THz grating fabricated by depositing a gold layer on the femtosecond micromachined SiO2 substrate. The morphology of the gold plated patterned substrate was studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM), while the quality of the chemical vapor deposition (CVD) graphene was evaluated by Raman spectroscopy. The electromagnetic (EM) response of the metasurface comprising the graphene sheet and the gold plated substrate was studied by THz time domain spectroscopy in the 100 GHz–1 THz frequency range. We employed the finite elements method (FEM) to model the metasurface EM response by adjusting the ac conductivity of the gold layer covering the patterned SiO2 substrate to reproduce the measured transmission/reflection spectra. The results of the numerical simulation reveal the impact of the imperfectness of the gold layer on the performance of the THz metasurface. The experimental results are well described in terms of the Drude–Smith model of metal conductivity that takes into account the anisotropic scattering of the carriers in thin metal films. 相似文献