If early caribbean philosophy is characterized by its pan-African flourishes, what is less well known is its flirtations with existentialism. Although c.L.R. James's 1965 Heideggerian reading of Wilson Harris'...
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If early caribbean philosophy is characterized by its pan-African flourishes, what is less well known is its flirtations with existentialism. Although c.L.R. James's 1965 Heideggerian reading of Wilson Harris's novel Palace of the Peacock and his 1966 lecture "Existentialism and Marxism" are cited in books on both James and Harris, oddly, there has been no substantial reading of Heidegger's own philosophy along with Palace of the Peacock, or, of James's misreading of Heidegger's technical term Dasein. In this article, I attempt that reading, while revealing a link between Dutch philosopher Baruch Spinoza, through existentialism, to Harris's work and thought. Harris's novel offers a radical critique of colonial racism through a re-working of Spinoza's metaphysics of Substance, and subsequently, although he only started the task, c.L.R. James's odd articulation of Harris with Heidegger is acute, notwithstanding existentialism's fall from fashion.
Background. Paraquat (PQ) is an effective and widely used herbicide and causes numerous fatalities by accidental or voluntary ingestion. However, neither the final cytotoxic mechanism nor effective treatments for PQ p...
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Background. Paraquat (PQ) is an effective and widely used herbicide and causes numerous fatalities by accidental or voluntary ingestion. However, neither the final cytotoxic mechanism nor effective treatments for PQ poisoning have been discovered. Phenotypic drug discovery (PDD), which does not rely on the molecular mechanism of the diseases, is having a renaissance in recent years owing to its potential to address the incompletely understood complexity of diseases. Herein, the c. elegans PDD model was established to pave the way for the future phenotypic discovery of potential agents for treating PQ poisoning. Methods. c. elegans were treated with PQ-containing solid medium followed by statistical analysis of worm survival, pharyngeal pumping, and movement ability. Furthermore, coenzyme Q10 (coQ10) was used to test the c. elegans model of PQ poisoning by measuring the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), mitochondrial morphology, and worm survival rate. Additionally, we used the classic mice model of PQ intoxication to evaluate the validity of the c. elegans model of PQ poisoning by measuring the effect of coQ10 as a potential antidote for PQ poisoning. Results. In the c. elegans model of PQ poisoning, 5 mg/mL PQ increased the levels of ROS, MDA content, mitochondrial fragments, which significantly shortened the lifespan, while coQ10 alleviated these phenotypes. In the mice model of PQ poisoning, coQ10 increased the chance of survival in PQ poisoned mice while reducing ROS, MDA content in lung tissue and inhibiting PQ-induced lung edema. Moreover, coQ10 alleviated the lung morphopathological changes induced by PQ. conclusion. Here we established a c. elegans model of PQ poisoning, whose validity was confirmed by the classic mice model of PQ intoxication.
c/c-Sic-Hfccomposites were prepared using reactive melt infiltration (RMI) under a vacuum (noted as HS-V) and normal pressure (noted as HS-NP), separately. The distribution of the introduced Sic and Hfcceramics can ...
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c/c-Sic-Hfccomposites were prepared using reactive melt infiltration (RMI) under a vacuum (noted as HS-V) and normal pressure (noted as HS-NP), separately. The distribution of the introduced Sic and Hfcceramics can be regulated by adjusting the RMI pressure. Different pressures of the environment at the high temperature stage led to the difference in volatilization of Si in the melt and the ratios of c and HfSi2 in unit volume on the surface of the sample, resulting in the different composition of the sample surface. A HfSi2-Hfc-Sic mixed layer was formed on the surface of HS-NP, while Hfccoating was formed on the surface of HS-V. HS-NP possessed better ablation performance than HS-V. After ablation for 120 s, its mass ablation rate decreased by 87.81%. The presence of HfSi2 improved the densification of HfO2 film, which made the ablation resistance of HS-NP better than HS-V. This work provides a guide for choosing an idea pressure condition during RMI to obtain c/c-Sic-Hfccomposites with high ablation resistance.
Herein, a new kind of metal organic framework (MOF)-based magnetic metal nanoparticle/carbon composite, hollow porous co/ccomposite (HP-co/c) with ordered macroporous (-60 nm) embedded in shell has been fabricated by...
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Herein, a new kind of metal organic framework (MOF)-based magnetic metal nanoparticle/carbon composite, hollow porous co/ccomposite (HP-co/c) with ordered macroporous (-60 nm) embedded in shell has been fabricated by low-temperature carbonization (500 degrees c) of ZIF-8@ZIF-67/SiO2 core@shell precursor and subsequent HF etching process. compared with its control sample of hollow co/c (H-co/c), HP-co/ccomposite displays significantly improved microwave absorbing properties in matter of both reflection loss (RL) and effective microwave absorbing bandwidth (EAB, RL < -10 dB). Especially, the corresponding EAB is up to7.64 GHz with filler loading of only 15 wt%. This superior microwave absorbing performance is ascribed to the stronger attenuation capability and better impedance matching characteristics induced by the ordered macropores in the hollow co/c shell. It is believed that this structural design strategy can be extended to prepare other MOFs-derived lightweight and broadband microwave absorbents at relatively low pyrolysis temperature.
The changes in microstructure and mechanical properties of the carbon fiber and their effects on c/Siccomposites were studied. The H, N and O atoms escaped and the carbon content in the carbon fiber increased when th...
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The changes in microstructure and mechanical properties of the carbon fiber and their effects on c/Siccomposites were studied. The H, N and O atoms escaped and the carbon content in the carbon fiber increased when the heat treatment temperature exceeds 1200 degrees c. Meanwhile, the growth of graphite crystallite leaded to stress concentration and reduced the tensile strength of carbon fiber to 2.98 GPa by 1200 degrees c heat treatment. The active atoms on the surface of the carbon fiber were reduced, thus weakening the bonding force between the carbon fiber and the pyrolyticcarbon interface layer and improving the pullout mechanism of the carbon fiber. This result was also observed by synchrotron radiation X-ray computed tomography. The flexural strength of the c/ Siccomposite increased from 300 MPa without treatment to 364 MPa after 1600 degrees c heat treatment.
Organotin(IV) chemistry is nowadays in a continuous expansion due to the biological and medicinal potential found for some of these species. Within this study, the cytotoxic activity of several organotin(IV) compounds...
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Organotin(IV) chemistry is nowadays in a continuous expansion due to the biological and medicinal potential found for some of these species. Within this study, the cytotoxic activity of several organotin(IV) compounds was investigated on two lung cancer cell lines (H522 and SK-MES-1) and on a normal lung cell line in order to have an overview of the toxicity and the selectivity of these derivatives. Moreover, the synthetic protocols, as well as the structural particularities of the novel organotin(IV) species, are also discussed. Hydrolysis of [2-{(cH2O)(2)cR}c6H4](2)SnPh2 [R = H (1), Me (2)] with p-toluenesulfonic acid as a proton source afford the expected derivatives [2-(OcR)c6H4](2)SnPh2 [R = H (3), Me (4)]. When hydrochloric acid is used in these reactions, a chlorine-phenyl exchange took place in addition to the removal of the acetal fragments and the following products [2-(OcR)c6H4](2)SnPhcl [R = H (5), Me (6)] were isolated. Treatment of 5 with 2 equiv of 3-aminomethylpyridine in neat affords the imino(aryl)tin compound 2-(3 '-PycH2NcH)c6H4](2)SnPhcl (7). The reaction between 6 and potassium nicotinate allows the isolation of the organotin(IV) carboxylate [2-{Oc (cH3)}c6H4](2)SnPh[O(O)cc5H4N-3] (8). compounds 1-8 were characterized by multinuclear NMR spectroscopy in solution, mass spectrometry, and IR spectroscopy, and their molecular structures were confirmed by X-ray diffraction analysis. compounds 1-8 were investigated for their antitumoral effects on Homo sapiens lung cancer cell lines (H522 and SK-MES-1) and on a normal bronchial epithelial cell line, BEAS-2B.
The cyclic and single ablation behavior of c/c-Zrc-Sic and c/c-Zrccomposites prepared by reactive melt infiltration were studied. The ablation resistance properties of cyclic ablation of 30 s x 4 and single ablation ...
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The cyclic and single ablation behavior of c/c-Zrc-Sic and c/c-Zrccomposites prepared by reactive melt infiltration were studied. The ablation resistance properties of cyclic ablation of 30 s x 4 and single ablation of 120 s was similar to that of 60 s x 4 and 240 s. The oxidation of the matrix and the peeling content of oxides are aggravated with the increased cyclic ablation numbers. Under the cyclic ablation mode, c/c-Zrc-Siccomposites showed lower mass loss than c/c-Zrccomposites. At the single ablation of 240 s, c/c-Zrc-Siccomposites showed desirable ablation resistance owing to the formation of an effective heat/oxygen protection layer on the ablated surface.
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