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The seeding of cells into an organ is an important step in cell therapy because the final functional properties of the organ are related to the initial cell distribution throughout the organ. However, vessel occlusion is a serious problem that prevents uniform distribution of the cells in the entire organ. Understanding the mechanism of vessel occlusion can help optimize the seeding process. In this study, the vessel occlusion phenomenon under perfusion conditions during cell seeding was investigated. First, we applied a microfluidic system that enabled the observation of the occlusion events during injection. Second, we applied a multiphase numerical model that can describe the cell–cell interactions and cell–fluid interactions to investigate the vessel occlusion phenomenon during the seeding process. In particular, the effects of cell concentration and flow rate were investigated. The results indicate the importance of cell–cell interactions and cell–vessel interactions for the occurrence of vessel occlusion. In addition, it is found that the probability of occurrence of vessel occlusion increases with the increase in cell concentration and decrease in flow rate. The simulation model can help determine the optimum parameters to enhance cell seeding efficiency.

This essay considers Deleuze and Guattari’s paradoxical claim that Marx’s critique of political economy implies as a universal history derived from the singular features of capitalism. In this critique, capitalism is defined by the commodity form, as a relationship of economic equivalence that replaces the bonds of dependence underlying other social formations. By negating relations of kinship and caste, capitalism reveals, a contrario, the universal foundation of other societies. As the “negative of all social formations,” capitalism conditions a universal history, defined, retrospectively, from the singular standpoint of a society, based upon the negation of kinship and caste. In this universal history, moreover, the negation of capitalism is identified with the possibility of a new and equally singular form of society. In Anti-Oedipus, the latter is defined as a “schizophrenic” condition liberated from the commodity as well as from the bonds of dependence that constituted the universal foundation of earlier societies.

This paper examines Jacques Derrida's deconstruction of Giorgio Agamben's account of the history of bio-politics in the Beast and the Sovereign. In this account, the ‘threshold of bio-political modernity’ is identified with the collapse of an allegedly immemorial distinction between life and the law. According to Derrida, however, this in-distinction between life and the law, which supposedly marks the historical emergence of the bio-political, is in fact an originary event. Agamben, therefore, announces a bio-political modernity that has always already existed. In this essay, I argue that Derrida, in the Beast and the Sovereign, fails to grasp the significance of one of the principal figures employed in Agamben's theory of the bio-political, the ‘threshold’. This figure, which Agamben opposes, elsewhere in his writings, to the Derridean notion of difference/deferral, does not refer to either an historical beginning or something that has always already existed. Rather, the threshold is defined as a particular moment in which an originary phenomenon becomes a decisive historical norm. In his ‘history’ of the bio-political, therefore, Agamben identifies the modernity of the latter in terms of the historical normalization of an in-distinction between law and life that has always already occurred.

The seeding of cells into an organ is an important step in cell therapy because the final functional properties of the organ are related to the initial cell distribution throughout the organ. However, vessel occlusion is a serious problem that prevents uniform distribution of the cells in the entire organ. Understanding the mechanism of vessel occlusion can help optimize the seeding process. In this study, the vessel occlusion phenomenon under perfusion conditions during cell seeding was investigated. First, we applied a microfluidic system that enabled the observation of the occlusion events during injection. Second, we applied a multiphase numerical model that can describe the cell-cell interactions and cell-fluid interactions to investigate the vessel occlusion phenomenon during the seeding process. In particular, the effects of cell concentration and flow rate were investigated. The results indicate the importance of cell-cell interactions and cell-vessel interactions for the occurrence of vessel occlusion. In addition, it is found that the probability of occurrence of vessel occlusion increases with the increase in cell concentration and decrease in flow rate. The simulation model can help determine the optimum parameters to enhance cell seeding efficiency.

A high-fidelity computational analysis carefully validated against concurrently obtained experimental results is employed to examine self-noise radiation of airfoils at transitional flow regimes, with a focus on elucidating the connection between the unsteady behavior of the laminar separation bubble (LSB) and the acoustic feedback-loop (AFL) resonant interactions observed in the airfoil boundary layers. The employed parametric study examines AFL sensitivity to the changes in the upstream flow conditions and the airfoil loading. Implicit Large-Eddy Simulations are performed for a NACA-0012 airfoil in selected transitional-flow regimes for which experimental measurements recorded characteristic multiple-tone acoustic spectra with a dual ladder-type frequency structure. The switch between the tone-producing and no-tone-producing regimes is traced to the LSB size and position as a function of the flow Reynolds number and the airfoil angle of attack, and further substantiated by the linear stability analysis. The results indicate a strong multi-tonal airfoil noise radiation associated with the AFL and attributed to the switch from the slowly-growing Tollmien–Schlichting to the fast-growing Kelvin–Helmholtz instabilities occurring in thin LSB regions when those are localized near the trailing-edge (TE) on either side of the airfoil. Such a process eventually results in the nonlinearly saturated flapping vortical modes (“rollers”) that scatter into acoustic waves at the TE.

Since the 1990s the Mekong River delta has suffered a large decline in sediment supply causing coastal erosion, following catchment disturbance through hydropower dam construction and sand extraction. However, our new geological reconstruction of 2500-years of delta shoreline changes show that serious coastal erosion actually started much earlier. Data shows the sandy coast bounding river mouths accreted consistently at a rate of +2 to +4 km2/year. In contrast, we identified a variable accretion rate of the muddy deltaic protrusion at Camau; it was 2/year before 1400 years ago but increased drastically around 600 years ago, forming the entire Camau Peninsula. This high level of mud supply had sharply declined by the early 20th century after a vast canal network was built on the delta. Since then the Peninsula has been eroding, promoted by the conjunction of mud sequestration in the delta plain driven by expansion of rice cultivation, and hysteresis of long-term muddy sedimentation that left the protrusion exposed to wave erosion. Natural mitigation would require substantial increases in sediment supply well above the pre-1990s levels.

Limited information is known about organophosphate esters (OPEs) in sediments of the Dong Nai River System (DNRS) in Vietnam and the influences of complex hydro-sedimentary dynamics on their fate. In this study, 48 surface sediment samples were collected from the Dong Nai-Soai Rap River and its tributary Vam Co River for the determination of 11 target OPEs, together with grain size and total organic carbon (TOC). The total concentrations of OPEs were in the range of 39.4 ng/g dw-373 ng/g dw (mean: 128 ng/g dw), and tris(1-chloro-2-propyl) phosphate (TCPP) was the predominant one with an average contribution of 81%, followed by tri-n-butyl phosphate (TNBP), tris(2-ethylhexyl) phosphate (TEHP). The composition profiles of OPEs at different locations of the DNRS showed no significant differences (p 0.05). In addition, the distribution of OPEs had been influenced by both human activities and the fluvial-tidal interactions. The highly frequent and various human activities in Ho Chi Minh City (HCMC) leaded to the highest total concentration of OPEs in the midstream site. Based on our dataset, TOC content and grain size of sediments had significant correlation with certain OPEs (p 0.05), and sediments with higher TOC content and finer grain size in the DNRS were more likely to be deposited in the downstream reach, contributing to the estuary of the DNRS was identified as another hotspot with the second highest concentration of OPEs. Furthermore, the distribution of OPEs in the transects had distinct characteristics, which reflected the joint influence of the human activities and fluvial-tidal interaction as well. However, the mechanism of their influence needed further investigation.

This essay proposes a reading of Nhất Linh’s “Going to the West” (Đi Tây, 1935). The travelogue presents a critique of colonialism that was prevalent among the interwar Vietnamese elite. In...