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101.
102.
Natalia Pozdnyakova Artem Pastukhov Marina Dudarenko Arsenii Borysov Natalia Krisanova Anastasia Nazarova Tatiana Borisova 《Microgravity science and technology》2017,29(1-2):133-144
Carbon is the most abundant dust-forming element in the interstellar medium. Tremendous amount of meteorites containing plentiful carbon and carbon-enriched dust particles have reached the Earth daily. National Institute of Health panel accumulates evidences that nano-sized air pollution components may have a significant impact on the central nervous system (CNS) in health and disease. During inhalation, nano-/microsized particles are efficiently deposited in nasal, tracheobronchial, and alveolar regions and can be transported to the CNS. Based on above facts, here we present the study, the aims of which were: 1) to upgrade inorganic Martian dust simulant derived from volcanic ash (JSC-1a/JSC, ORBITEC Orbital Technologies Corporation, Madison, Wisconsin) by the addition of carbon components, that is, nanodiamonds and carbon dots; 2) to analyse acute effects of upgraded simulant on key characteristics of synaptic neurotransmission; and 3) to compare above effects with those of inorganic dust and carbon components per se. Acute administration of carbon-containing Martian dust analogues resulted in a significant decrease in transporter-mediated uptake of L-[14C]glutamate (the major excitatory neurotransmitter) and [3H]GABA (the main inhibitory neurotransmitter) by isolated rat brain nerve terminals. The extracellular level of both neurotransmitters increased in the presence of carbon-containing Martian dust analogues. These effects were associated with action of carbon components of upgraded Martian dust simulant, but not with its inorganic constituent. This fact indicates that carbon component of native Martian dust can have deleterious effects on extracellular glutamate and GABA homeostasis in the CNS, and so glutamate- and GABA-ergic neurotransmission disballansing exitation and inhibition. 相似文献
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Tatiana Lopes Fialho Evandro Martins Arlan Caldas Pereira Silveira Carolina Rodrigues de Jesus Silva Pierre Schuck 《Drying Technology》2018,36(8):922-931
Industrial production of lactose hydrolyzed milk powder (LHMP) remains challenging. Due to the presence of the monosaccharides glucose and galactose, lactose-free powders tend to suffer stickiness, caking, and browning during drying and storage. We sought to find ideal conditions spray dryer inlet air temperature (θair,in) and concentrated milk flow rate (mCM) for LHMP production. We tested θair,in settings of 115–160°C and mCM of 0.3–1.5?kg?·?h?1, and also applied mass and energetic balances. LHMP generally exhibited higher mass and energetic losses than the control (milk powder containing lactose), as a consequence of the relatively low dryability of LHMP. For a lab scale spray dryer, the ideal conditions settings for LHMP production were θair,in?=?145?±?2°C and mCM?=?1.0?kg?·?h?1, taking into account the mass yield and energetic cost (kJ?·?kg?1 of powder) of the process. These ideal conditions are a potential tool for the industrial development of lactose-free dairy powders. 相似文献
106.
Tatiana Moreira de Souza 《Housing Studies》2019,34(9):1521-1542
AbstractThis article draws on in-depth research on the nature and intensity of neighbour relations in an area in Peckham, London, which underwent urban regeneration aimed at improving the urban environment and increasing the area’s tenure mix. Drawing on the literature on neighbouring, the article explores residents’ perceptions and attitudes towards their neighbours and the dynamics of their routine interactions. Despite findings pointing towards a general atmosphere of cordiality and solidarity, interactions were casual, coexisted with prejudiced views towards certain groups and areas, and were viewed by residents as part of their everyday social practices of community. As a result, very little else was exchanged between tenures, putting into question some policy assumptions that the increased physical proximity between housing tenures can potentially lead to instrumental interaction that can benefit low-income households in social housing. Reflecting on these findings, the article discusses some implications that have relevance for policy and research. 相似文献
107.
We consider infrastructure-based mobile networks that are assisted by a single relay transmission where both the downstream destination and relay nodes are mobile. Selecting the optimal transmission path for a destination node requires up-to-date link quality estimates of all relevant links. If the relay selection is based on link quality measurements, the number of links to update grows quadratically with the number of nodes, and measurements need to be updated frequently when nodes are mobile. In this paper, we consider a location-based relay selection scheme where link qualities are estimated from node positions; in the scenario of a node-based location system such as GPS, the location-based approach reduces signaling overhead, which in this case only grows linearly with the number of nodes. This paper studies these two relay selection approaches and investigates how they are affected with varying information update interval, node mobility, location inaccuracy, and inaccurate propagation model parameters. Our results show that location-based relay selection performs better than SNR-based relay selection at typical levels of location error when medium-scale fading can be neglected or accurately predicted. 相似文献
108.
Giannakopoulou F Haidouti C Chronopoulou A Gasparatos D 《Journal of hazardous materials》2007,149(3):553-556
In the present study we investigated the sorption behavior of Cs in four different soils (sandyloam, loam, clayloam and clay) by using batch experiment. Cs sorption characteristics of the studied soils were examined at 4 mgL(-1) Cs concentration, at various pH levels, at room temperature and with 0.01 M CaCl(2) as a background electrolyte. Among different soils the decrease of k(d) (distribution coefficient) of cesium, at all pH levels, followed the sequence sandyloam > loam > clayloam > clay, indicating that the particle size fractions and especially the clay content plays predominant role on sorption of Cs. The effect of pH on cesium sorption displays a similar pattern for all soils, depending on soil type. At acid pH levels less cesium was sorbed, due to a greater competition with other cations for available sorption sites. The maximum sorption of Cs was observed at pH 8, where the negative charge density on the surface of the absorbents was the highest. For all soils was observed significantly lower Cs sorption at pH 10. 相似文献
109.
Abstract and Key Results
相似文献
▪ | Subsidiary managers are faced with complex managerial roles involving both the interests of the multinational corporation (MNC) and the subsidiary. We suggest complex roles are best fulfilled when managers develop dual organizational identification towards both entities. |
▪ | Based on a conceptualization of dual organizational identification in terms of relative magnitude, we test the effect of dual identification on subsidiary manager roles and role conflict. |
▪ | Results indicate that high identification with both entities is associated with high role fulfillment and that similarity in organizational identities directly affects role conflict. |
110.
Bastiaans MJ Alieva T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(4):1053-1062
Based on the eigenvalues of the ray transformation matrix, a classification of ABCD systems is proposed and some nuclei (i.e., elementary members) in each class are described. In the one-dimensional case, possible nuclei are the magnifier, the lens, and the fractional Fourier transformer. In the two-dimensional case we have-in addition to the obvious concatenations of one-dimensional nuclei-the four combinations of a magnifier or a lens with a rotator or a shearing operator, where the rotator and the shearer are obviously inherently two-dimensional. Any ABCD system belongs to one of the classes described in this paper and is similar (in the sense of matrix similarity of the ray transformation matrices) to the corresponding nucleus. Knowledge of a nucleus may be helpful in finding eigenfunctions of the corresponding class of first-order optical systems: one only has to find eigenfunctions of the nucleus and to determine how these functions propagate through a first-order optical system. 相似文献