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61.
The presence of bioactive interleukin-1 (IL-1) in various brain regions (cerebellum, cortex, brainstem, diencephalon or hippocampus) after either intraperitoneal (i.p.) or intraventricular (i.c.v.) injection of lipopolysaccharide (LPS) was studied in the rat. To detect IL-1, extracellular fluid and cell lysate were fractionated by gel exclusion chromatography and fractions tested for thymocyte stimulation; presence of IL-1 was confirmed by blockade of stimulation by addition to the assay of a monoclonal antibody (mAb) to IL-1 receptor. When LPS was infused i.c.v., IL-1 was detected in the brainstem and diencephalon 2 h after injection, and in all the brain regions except cerebellum 6 h after injection; IL-1 was not detected in the plasma of these animals. When LPS was injected i.p., IL-1 was detected in the plasma but not in the brain 2 h after the injection, and in all brain regions but not in the plasma 6 h after the injection. In all of these cases, IL-1 was found in extracellular fluid; in some cases (cortex, cerebellum) cell lysate of the region did not produce detectable bioactivity, thereby indicating that IL-1 in these brain regions is processed to active peptide during release, as has been reported in the periphery. In those cases where bioactivity was detected in cell lysate (brainstem, diencephalon), bioactivity was not blocked by IL-1 receptor mAb, indicating presence of a non-IL-1 stimulating factor. These results further support the idea that IL-1 is secreted by cells in the brain, and indicate that it is found in the extracellular fluid of many brain regions following an appropriate stimulus in the periphery as well as in the brain.  相似文献   
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63.
Breast cancer accounts for the first highest mortality rate in India and second in world. Though current treatment strategies are effectively killing cancer cells, they also end in causing severe side effects and drug resistance. Curcumin is a nutraceutical with multipotent activity but its insolubility in water limits its therapeutic potential as an anti‐cancer drug. The hydrophilicity of curcumin could be increased by nanoformulation or changing its functional groups. In this study, curcumin is loaded on mesoporous silica nanoparticle and its anti‐cancer activity is elucidated with MCF‐7 cell death. Structural characteristics of Mobil Composition of Matter ‐ 41(MCM‐41) as determined by high‐resolution transmission electron microscopy (HR‐TEM) shows that MCM‐41 size ranges from 100 to 200 nm diameters with pore size 2–10 nm for drug adsorption. The authors found 80–90% of curcumin is loaded on MCM‐41 and curcumin is released efficiently at pH 3.0. The 50 µM curcumin‐loaded MCM‐41 induced 50% mortality of MCF‐7 cells. Altogether, their results suggested that increased curcumin loading and sustained release from MCM‐41 effectively decreased cell survival of MCF‐7 cells in vitro.Inspec keywords: cancer, cellular biophysics, nanoparticles, nanomedicine, biomedical materials, polymers, mesoporous materials, transmission electron microscopy, drugs, adsorptionOther keywords: polyethylenimine‐modified curcumin‐loaded mesoporus silica nanoparticle, MCF‐7 cell line, breast cancer, cancer cells, drug resistance, multipotent activity, therapeutic potential, anticancer drug, mesoporous silica nanoparticle, MCF‐7 cell death, high‐resolution transmission electron microscopy, drug adsorption, curcumin‐loaded MCM‐41, nutraceutical curcumin, size 2 nm to 10 nm, size 100 nm to 200 nm  相似文献   
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Organic solar cells were fabricated with two new imidazolin-5-one molecules as active layers. The use of imidazolin-5-ones, derivatives of a biomolecule chromophore, for photovoltaic applications is particularly attractive due to its biodegradable nature and tunable properties. Single-layer devices with two analogues of imidazolin-5-ones were prepared and characterized. Devices fabricated with one of the molecules as the active layer showed a maximum Jsc of 0.52 μA cm−2 and Voc of 0.68 V at an incident power of 20.32 mW cm−2, while the other set of devices showed a maximum Jsc of 0.63 μA cm−2 and Voc of 0.57 V at the same incident power.  相似文献   
66.
In analyzing the human tendency to treat computers as social actors (CASA), researchers tend to rule out the anthropomorphism explanation because anthropomorphism is understood to be “a sincere, conscious belief” that computers are human and/or deserving of human attributions. But, does anthropomorphism have to be necessarily mindful? Could it not also be a mindless tendency, especially given that most of us have somewhat long associations with our computers and have built human-like bonds with them? We examined these questions empirically by investigating whether the user tendency to treat computers as human beings is conscious (mindful) or non-conscious (mindless). We manipulated two variables (presence/absence of human-like agent and the low/high interactivity) on a health website and experimentally investigated whether they serve as anthropomorphic cues to trigger mindful attributions of human-ness to the website or mindless evaluations of the site in human terms. We found evidence for mindless anthropomorphism, with implications for user judgments of credibility of information on the site.  相似文献   
67.
Prototype Fast Breeder Reactor (PFBR) has two independent fast acting diverse shutdown systems. The absorber rod of the first system is called Control & Safety Rod (CSR). CSR and its Drive Mechanism (CSRDM) are used for reactor control and for safe shutdown of the reactor by scram action. In view of the safety role, the qualification of CSRDM is one of the important requirements.CSR & CSRDM were qualified in two stages by extensive testing. In the first stage, the critical subassemblies of the mechanism, such as scram release electromagnet, hydraulic dashpot & dynamic seals and CSR subassembly, were tested and qualified individually simulating the operating conditions of the reactor. Experiments were also carried out on sodium vapour deposition in the annular gaps between the stationary and mobile parts of the mechanism.In the second stage, full-scale CSRDM and CSR were subjected to all the integrated functional tests in air, hot argon and subsequently in sodium simulating the operating conditions of the reactor and finally subjected to endurance tests. Since the damage occurring in CSRDM & CSR is mainly due to fatigue cycles during scram actions, the number of test cycles was decided based on the guidelines given in ASME, Section III, Div. 1. The results show that the performance of CSRDM & CSR is satisfactory. Subsequent to the testing in sodium, the assemblies having contact with liquid sodium/sodium vapour were cleaned using CO2 process and the total cleaning process has been established, so that the mechanism can be reused in sodium. The various stages of qualification programmes have raised the confidence level on the performance of the system as a whole for the intended and reliable operation in the reactor.  相似文献   
68.
Nitrogen-doped graphene–silver nanoparticle hybrids were prepared by thermal treatment of graphite oxide (GO) with glycine and silver nitrate at 500 °C. Glycine was used to reduce the nitrate ions, resulting in the decomposition of a glycine–nitrate mixture near 200 °C. The products of decomposition act as sources for nitrogen doping. The thermal treatment of a mixture of GO, glycine and silver nitrate results in the formation of silver nanoparticles at 100 °C, promotes the reduction of GO near 200 °C, and generates pyrrolic and pyridinic type nitrogen doping in graphene at 300 and 500 °C, respectively. The atomic percentage of nitrogen in as-prepared sample is about 13.5%. This approach opens up a new possibility for the synthesis of nitrogen-doped graphene decorated with various metallic nanoparticles, which could find important applications in the fields of energy storage and conversion devices.  相似文献   
69.
Windowing techniques have been widely used for preprocessing of samples before fast Fourier transform (FFT) in real time spectral analysis to minimize spectral leakage and picket fence effect. Among all popular window functions, Kaiser-Bessel window is an obvious choice for its better spectral characteristics. In this paper, CORDIC (CO-ordinate Rotation DIgital Computer) based VLSI architecture for implementing Kaiser-Bessel window has been proposed for real time applications. The parallel-pipelined technique has been adopted for the present design to ensure high throughput. Various architectural design and implementation issues have been discussed. The physical synthesis for ASIC implementation of proposed architecture using Synopsys design compiler(Design Vision) and commercially available 0. 18 μm CMOS yields the core area of 52 mm 2and worst case dynamic power of 890 mW at an operating frequency and voltage of 400 MHz and 1.8 V respectively.  相似文献   
70.
The Extended Euclidean algorithm for matrix Padé approximants is applied to compute matrix Padé approximants when the coefficient matrices of the input matrix polynomial are triangular. The procedure given by Bjarne S. Anderson et al. for packing a triangular matrix in recursive packed storage is applied to pack a sequence of lower triangular matrices of a matrix polynomial in recursive packed storage. This recursive packed storage for a matrix polynomial is applied to compute matrix Padé approximants of the matrix polynomial using the Matrix Padé Extended Euclidean algorithm in packed form. The CPU time and memory comparison, in computing the matrix Padé approximants of a matrix polynomial, between the packed case and the non-packed case are described in detail.  相似文献   
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