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111.
Wireless Personal Communications - This paper proposes a novel tri-band reconfigurable UWB antenna using a balun structure. The proposed UWB antenna achieves tri-band frequency of operation in two... 相似文献
112.
Pachiappan Perumal Rajamani Sowmiya Sundaram Prasanna kumar Sundaram Ravikumar Paramasivam Deepak Govindasamy Balasubramani 《Natural product research》2018,32(11):1316-1319
The brown seaweed, Sargassum linearifolium (Turner) C. Agardh, 1820 is commonly available along the south-east coast of India. Its compound fucosterol was isolated and confirmed through spectral characterisation and chemical transformation methods. The antiplasmodial effect of the isolated fucosterol was investigated against the 3D7 chloroquine sensitive Plasmodium falciparum strain, parasitaemia percentage was determined at 48 h and morphological change was studied through microscopic examination after Giemsa staining. A perceptible antiplasmodial effect was produced by fucosterol compound against the P. falciparum and positive control, chloroquine with the IC50 values (μg/mL) of 7.48 and 12.81, respectively. Fucosterol showed higher antiplasmodial activity as compared to chloroquine. It is inferred that both the fucosterol and chloroquine could have inhibited the schizont stage of the parasite during the intra-erythrocyte asexual development. The findings underline the usefulness of the seaweed-based fucosterol and further studies are warranted. 相似文献
113.
Summary Letf, G1 × G2 C, where G
i
(i = 1, 2) denote arbitrary groups and C denotes the set of complex numbers. The general solutions of the following functional equationsf(x
1
y
1
,x
2
y
2
) +f(x
1
y
1
,x
2
y
2
-1
) +f(x
1
y
1
-1
,x
2
y
2
) +f(x
1
y
1
-1
,x
2
y
2
-1
) =f(x
1
,x
2
)F(y
1
,y
2
) +F(x
1
,x
2
)f(y
1
,y
2
) (1) andf(x
1
y
1
,x
2
y
2
) +f(x
1
y
1
,x
2
y
2
-1
) +f(x
1
y
1
-1
,x
2
y
2
) +f(x
1
y
1
-1
,x
2
y
2
-1
) =f(x
1
,x
2
)f(y
1
,y
2
) +F(x
1
,x
2
)F(y
1
,y
2
) (2) are determined assuming thatf satisfies the conditionf(x
1y1z1, x2) = f(x1z1y1, x2), f(x1, x2y2z2) = f(x1, x2z2y2) (C) for allx
i, yi, xi Gi (i = 1, 2). The functional equations (1) and (2) are generalizations of the well known rectangular type functional equationf(x
1 + y1, x2 + y2) + f(x1 + y1, x2 – y2) + f(x1 – y1, x2 + y2) + f(x1 – y1, x2 – y2) = 4f(x1, x2) studied by J. Aczel, H. Haruki, M. A. McKiernan and G. N. Sakovic in 1968. 相似文献
114.
Ju-Wook Jang Choi S.B. Prasanna V.K. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2005,13(11):1305-1319
We develop new algorithms and architectures for matrix multiplication on configurable devices. These have reduced energy dissipation and latency compared with the state-of-the-art field-programmable gate array (FPGA)-based designs. By profiling well-known designs, we identify "energy hot spots", which are responsible for most of the energy dissipation. Based on this, we develop algorithms and architectures that offer tradeoffs among the number of I/O ports, the number of registers, and the number of PEs. To avoid time-consuming low-level simulations for energy profiling and performance prediction of many alternate designs, we derive functions to represent the impact of algorithm design choices on the system-wide energy dissipation, area, and latency. These functions are used to either optimize the energy performance or provide tradeoffs for a family of candidate algorithms and architectures. For selected designs, we perform extensive low-level simulations using state-of-the-art tools and target FPGA devices. We show a design space for matrix multiplication on FPGAs that results in tradeoffs among energy, area, and latency. For example, our designs improve the energy performance of state-of-the-art FPGA-based designs by 29%-51% without any increase in the area-latency product. The latency of our designs is reduced one-third to one-fifteenth while area is increased 1.9-9.4 times. In terms of comprehensive metrics such as Energy-Area-Time, our designs exhibit superior performance compared with the state-of-the-art by 50%-79%. 相似文献
115.
Glycogen synthase kinase-3, a serine/threonine kinase, has been implicated in a wide variety of pathological conditions such
as diabetes, Alzheimer’s disease, stroke, bipolar disorder, malaria and cancer. Herein we report 3D-QSAR analyses using CoMFA
and CoMSIA and molecular docking studies on 3-anilino-4-phenylmaleimides as GSK-3α inhibitors, in order to better understand
the mechanism of action and structure-activity relationship of these compounds. Comparison of the active site residues of
GSK-3α and GSK-3β isoforms shows that all the key amino acids involved in polar interactions with the maleimides for the β
isoform are the same in the α isoform, except that Asp133 in the β isoform is replaced by Glu196 in the α isoform. We prepared
a homology model for GSK-3α, and showed that the change from Asp to Glu should not affect maleimide binding significantly.
Docking studies revealed the binding poses of three subclasses of these ligands, namely anilino, N-methylanilino and indoline
derivatives, within the active site of the β isoform, and helped to explain the difference in their inhibitory activity. 相似文献
116.
117.
The present study was structured to investigate the anti-inflammatory potential of the extracts, fractions and compounds isolated from Carissa carandas (L.) roots. Bioassay guided fractionation of methanol extract based on inhibitory potential towards proinflammatory mediators (TNF-α, IL-1β and nitric oxide (NO)) led to the identification of stigmasterol (1), lupeol (2), oleanolic acid (3), carissone (4) and scopoletin (5) as potential anti-inflammatory agents. Carissone (4) (IC50 = 20.1 ± 2.69 μg/mL) and scopoletin (5) (IC50 = 24.6 ± 1.36 μg/mL) exhibited significant inhibition of NO production comparable to specific NO inhibitor (L-NAME; IC50 = 19.82 ± 1.64 μg/mL) without affecting the cell viability. Also, 4 and 5 at a concentration of 30 μM were found to inhibit 41.88–53.44% of TNF-α and IL-1β. To the best of our knowledge, this is the first report displaying the anti-inflammatory effects of C. carandas (L.) roots, partially mediated by inhibition of TNF-α, IL-1β and NO. 相似文献
118.
119.
Prof. Dr. A. Prasanna de Silva 《化学:亚洲杂志》2011,6(3):750-766
Chemists are now able to emulate the ideas and instruments of mathematics and computer science with molecules. The integration of molecular logic gates into small arrays has been a growth area during the last few years. The design principles underlying a collection of these cases are examined. Some of these computing molecules are applicable in medical‐ and biotechnologies. Cases of blood diagnostics, ‘lab‐on‐a‐molecule’ systems, and molecular computational identification of small objects are included. 相似文献
120.
Sudhir Kumar Barik Sudeshna Banerjee Soma Bhattacharjee Sujoy Kumar Das Gupta Sasmita Mohanty Bimal Prasanna Mohanty 《Applied biochemistry and biotechnology》2013,171(4):1011-1021
Detection of species-specific sarcoplasmic peptides can be used as proteomic markers for fish food authentication and identification of species of origin in processed products. In the present study, proteomics technology was employed for differential characterization of sarcoplasmic peptides of two closely related fish species, Sperata seenghala and Sperata aor. Species-specific peptides were searched in white muscle extracts of the two species for identification of unique peptides that might aid in differentiation of the species, under two-dimensional gel electrophoresis platform. A total of 19 proteins were identified by combined matrix-assisted laser desorption ionization time-of-flight mass spectrometry and liquid chromatography-tandem mass spectrometry, of which nine and two proteins were found to be unique to S. seenghala and S. aor, respectively. One of the proteins, triosephosphate isomerase (TPI) was found to have three isoforms, out of which two were specific to S. aor, and one was specific to S. seenghala. All the three isoforms of TPI were present in the mixed samples of raw protein extracts of S. seenghala and S. aor, an observation that can be exploited to differentiate between the species and detection of deceptive practices of fraudulent substitution of commercially valuable fish species with inferior ones and differential characterization between closely related fish species. 相似文献