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Energy devices with high energy/power density are the need of the day, and to achieve the same, electrolytes with faster ion transport and wider electrochemical stability window are required. Polymer-in-salt electrolytes (PISEs) are predicted to have the better required electrochemical properties in comparison to salt-in-polymer electrolytes (SIPEs), but desired success is still to be achieved due to recrystallization problems. PISEs suffer from poor mechanical and/or electrochemical properties along with aging effects as well; hence, special efforts are required to reduce the crystallinity of PISEs. The present paper discusses a crosslinked corn starch complexed with Mg(ClO4)2 which not only has desired electrochemical properties but is also flexible. XRD study confirms the absence of crystalline nature, without any extra efforts to reduce it. Synthesized PISEs have high conductivity (~0.01 Scm−1), wide ESW (> 3 V), and low relaxation time (µs) along with being economical. Supercapacitors fabricated using this novel PISE with laboratory synthesized activated carbon (from leaves and corn starch) have shown good specific capacitance (~ 20 Fg−1 and ~ 45 Fg−1, respectively). The power density is of the order of kW kg−1, which is quite high in comparison to other reports. The shape of CV and LSV is strongly influenced by the salt concentration, i.e., by the ion-cluster size, and is also affected by the volume/size of the activated carbon pores. [ABSTRACT FROM AUTHOR]

Polymer‐in‐salt‐electrolytes (PISEs) are an important class of electrolytes as they carry the promise of faster and single ion transport. Unfortunately, due to unavailability of a suitable polymer host PISE has still not reached to commercial level. In the present work, using a novel synthesis protocol developed by the group, glutaraldehyde crosslinked wheat starch has been successfully modified with sodium iodide (NaI) to synthesize a flexible PISE membrane with desired electrochemical properties. Present paper reports the effect of crosslinker and exposure to high humidity ambience on electrochemical and morphological properties. It has been established that on exposure to higher humidity atmosphere starch‐based PISEs stabilize at lower resistance value, but with higher ion relaxation time, which indicates that effect of high humidity treatment is more on salt dissociation instead of assisting the ion transport. The studied materials have conductivity ≈0.01 S cm−1 range with ESW >2.5 V, ensuring its usability in electrochemical devices. The developed synthesis protocol does not require any complicated synthesis route and/or sophisticated instrument hence the overall process is economical also, adding up to its potentiality for energy device fabrication. [ABSTRACT FROM AUTHOR]

Isabel Hofmeyr's latest book begins with stories around and about the colonial port, though the initial spotlight is on decidedly nonnarrative texts such as classification lists of cargo items, customs handbooks, and what she intriguingly calls the "book-as-form," namely diaries and registers. These, she says, "offered one unwitting model of colonial writing in which a template from the metropolis was filled with local scribblings" (12). The port is, by definition, a liminal, watery, zone, with uncertain borders between land and sea, but which often acts as the site of border policing that regulates entry into and out of the colony and nation-state. It is a powerfully evocative place around which to set Hofmeyr's ambitious and wide-ranging book, and the port's polysemous implications allow her to intervene across a series of disparate fields: climate humanities, postcolonial studies, object-oriented ontology, South African literary histories, and studies of custom and copyright. It is a masterly and original revisioning of what it means to do book history, offering a radically new method of reading. Even more importantly, it proposes a new definition of the book as object: as customs cargo, as charismatic "thing" that creates literary canonicity far from the metropole, and as an epidemiological vector of "contamination" in the mind of the colonial customs official on the alert for seditious or obscene texts, among other suggestive meanings. [ABSTRACT FROM AUTHOR]

In this paper, we analyse the performance of infrastructure-based fixed relay with multi-antenna in cognitive radio. We derive the mathematical expression for detection probability of single cooperative relay system over Rayleigh fading channel. Relay and fusion centre may perform either selection combining or maximal ratio combining of the signals. Effect of number of relay antennas for all four combinations of combining schemes has been analysed and as expected, increase in relay diversity improves the sensing performance. This is because, on installing more number of receiving antennas on the relay, it's participation increases, so the detection performance also improves. In the non-cooperative system also, the performance improves on increasing the diversity order but on the other hand, this increment imposes burden on the fusion centre. Whereas in multi-antenna cooperative relay system, the burden of relay gets transferred on relay node and the fusion centre takes advantage of increased diversity order of relay. For cooperative spectrum sensing, we have used soft decision combining scheme in which secondary users send their test statistics calculated from their local observations. [ABSTRACT FROM AUTHOR]

Recent studies suggest that lysophosphatidic acid (LPA) and its G protein-coupled receptors (GPCRs) [LPA.sub.1], [LPA.sub.2], or [LPA.sub.3] may play a role in the development of several types of cancers, including colorectal cancer. However, the specific receptor subtype(s) and their signal-transduction pathways responsible for LPA-induced cancer cell proliferation have not been fully elucidated. We show by specific RNA interference (RNAi) that [LPA.sub.2] and [LPA.sub.3] but not [LPA.sub.1] are targets for LPA-induced proliferation of HCT116 and LS174T colon cancer cells. We determined that LPA-induced colon cancer cell proliferation requires the [beta]-catenin signaling pathway, because knockdown of [beta]-catenin by RNAi abolished LPA-induced proliferation of HCT116 cells. Moreover, LPA activates the main signaling events in the [beta]-catenin pathway: phosphorylation of glycogen synthase kinase 3[beta] (GSK3[beta]), nuclear translocation of [beta]-catenin, transcriptional activation of T cell factor (Tcf)/lymphoidenhancer factor (Lef), and expression of target genes. Inhibition of conventional protein kinase C (cPKC) blocked the effects, suggesting its involvement in LPA-induced activation of the [beta]-catenin pathway. Thus, [LPA.sub.2] and [LPA.sub.3] signal the proliferation of colon cancer cells through cPKC-mediated activation of the [beta]-catenin pathway. These results link LPA and its GPCRs to cancer through a major oncogenic signaling pathway. colon cancer cell | G protein-coupled receptor

This essay argues that Antonio Gramsci should be considered a postcolonial thinker. This is not an exercise in presenting the "legacy" of a European Marxist's thought in the Third World. The aim here, rather, is to determine how Gramscian thought can be read as anticolonial, and how he related empire to the hegemonic-subaltern dialectic that structured his political theories. I engage with Joseph Buttigieg's well-known essay "Gramsci's Method" in order to explore how the philological method adopted in the Prison Notebooks offers several important insights for postcolonial studies, and bears obvious connections to the work of the Subaltern Studies historians, especially in terms of how it is central to the retrieval of subaltern pasts. I further argue that Gramsci's interest in the national-popular and in forms of progressive nationalism that were grounded in internationalist solidarity suggests strong connections with Third Worldist theories of liberation struggles, such as tricontinentalism and the work of Frantz Fanon. Applying Buttigieg's way of reading of Gramsci's anti-dogmatic philological method to Third Worldism allows us to see how it renovated Marxism's revolutionary aims and emancipatory futures, and ultimately helped to decolonize Marxism. [ABSTRACT FROM AUTHOR]

This article examines the feminist, communist and antifascist campaigner Sylvia Pankhurst as a postcolonial intellectual for our times. A forgotten figure in the history of anticolonialism, Pankhurst was active in the suffragette movement and then the communist movement, before devoting her political energies to supporting Ethiopia against the Italian invasion led by Mussolini in 1935. Pankhurst's broadsheet New Times and Ethiopia News published articles denouncing the Italian occupation as well as writing by prominent African and Asian anticolonial voices. Through the analysis of Pankhurst, this article argues for an understanding of the postcolonial intellectual as a partisan who cuts across civilizational divides, bringing together metropolitan and colonial networks of resistance. I draw on Carl Schmitt's Theory of the Partisan in which he describes the partisan, exemplified in the political combatant of the wars of decolonization, as the emblematic figure of twentieth-century warfare. I adapt Schmitt's theory to read Pankhurst's militancy in favour of Ethiopia in order to argue that the partisan is not only an insurgent fighter but an individual who takes sides in the interconnected struggles against colonialism and fascism. I thus gesture to the possibility of a global theory of resistance. [ABSTRACT FROM AUTHOR]

A 3 × 3 slotted circular Electromagnetic Band gap based Metasurface (SCEBG-MS) has been presented in this article, which enhances the performance of a circularly polarized (CP) patch antenna by improving its impedance bandwidth, axial ratio bandwidth and gain. The proposed antenna is having a low profile of 0.065 λo (λo is the free-space wavelength at center frequency of 6.16 GHz) with ground size selection of 30 × 30 mm. The prototype antenna achieves a measured −10 dB impedance bandwidth of 37% (5.02–7.30 GHz) and measured 3-dB axial ratio bandwidth of 5.9% (5.24–5.56 GHz). Furthermore, the antenna yields a good peak gain of 6.6 dBic in the CP bandwidth which makes it a promising candidate for Wireless Local Area Network (WLAN) applications. Experimental results obtained from the fabricated prototype closely matched with the simulated results. [ABSTRACT FROM AUTHOR]

In this article, a new compact Circularly Polarized Antenna with wide operating bandwidth is proposed. The proposed structure consists of a Modified Circular Split Ring Resonator (MCSRR) as the radiating patch, which is fed by coplanar waveguide and loaded with 2 × 2 closed-ring resonantor (CRR) array on its FR4 epoxy substrate. The dimensions of the antenna are 0.329 λo x 0.329 λo x 0.024 λo (λo stands for the free space wavelength at center frequency of 4.94 GHz).The implementation CRR on modified printed monopole antenna leads to a wide measured impedance bandwidth of 2726 MHz with a peak gain of 5.09dBi and efficiency of 96.3% in the operating bandwidth. A prominent feature of the proposed antenna is that dual 3-dB axial ratio bandwidth of 430 MHz and 670 MHz is observed in the operating band, and thus, making it to be a promising candidate for recent day wireless applications. The simulated results was verified by measuring the characteristics of the fabricated antenna; the obtained results showed a good matching with the simulated results. [ABSTRACT FROM AUTHOR]

In this article, a hexagonal ring electromagnetic band gap (HREBG) structure‐based circularly polarized (CP) slot antenna for improving performance is proposed. The proposed antenna has a compact structure with a low profile of 0.517λo × 0.517λo × 0.055λo (λo stands for the free space wavelength at 5.10 GHz), is coplanar waveguide fed, and comprises of a circular microstrip patch with a T‐shaped slot. An inclined coupling slot loaded feed line is used on the ground for the generation of CP. Furthermore, eight HREBG's are implemented on the substrate to enhance the performance of the antenna, thereby achieving a measured impedance bandwidth of 18%, 3‐dB axial ratio bandwidth of 6.4%, and a peak gain of 5.93 dBi in the operating bandwidth. A close agreement is reached between the experimental results and the simulated results to verify the proposed antenna's performance. [ABSTRACT FROM AUTHOR]

In this paper, an electromagnetic band gap (EBG) metasurface (MS) superstrate-based circularly polarized antenna for the WiMAX (3.5 GHz) band is proposed. The proposed structure comprises a 2 × 2 slot-loaded rectangular patch MS array that can be perceived as a polarization-dependent EBG MS superstrate. Furthermore, to achieve circular polarization, the proposed antenna has an inclined coupling slot onto the ground with a conventional coplanar waveguide feed line. The proposed antenna has a compact structure with a low profile of 0.037 λ 0 (λ 0 stands for the free-space wavelength at 3.48 GHz) and a ground size of 30 × 30 mm2. The measured results show that the −10 dB impedance bandwidth for the proposed antenna is 34.6% and the 3-dB axial ratio (AR) bandwidth is 6.8% with a peak gain of 3.91 dBi in the desired operating band. Good agreement between the simulated and the measured results verifies the performance of the proposed antenna. [ABSTRACT FROM AUTHOR]

In this article, a new structure comprising of a novel compact slot loaded polarization dependent Electromagnetic Band Gap structure (SLPDEBG), which enhances the performance of circularly polarized rotated square patch antenna by placing SLPDEBG unit cells around it, has been designed. The proposed antenna, having dimensions 0.640 λo x 0.640 λ x 0.0128 λo (λo stands for the free space wavelength at 2.39 GHz), shows that the measured impedance bandwidth and AR bandwidth is 120 MHz and 50 MHz, respectively, with a peak gain of 3.52 dB. Some prominent features of the proposed structure are: front to back ratio of 64, 3 db, beamwidth of 92° at xz-plane and 74° at yz-plane. This prototype antenna finds its application in wireless communication of ISM band. Good performance of the proposed antenna is verified by the close agreement between the simulated and measured results. [ABSTRACT FROM AUTHOR]

Being eco-friendly, cost-effective, easy to synthesize and handle, starch-based electrolytes have tremendous advantages for electrochemical device fabrications. Starch electrolytes synthesized by crosslinking process result in stable, flexible, free-standing films which can be molded in different shapes and sizes. Rice starch–based material, prepared using glutaraldehyde as crosslinker and NaClO4 as ion-providing salt, resulted in high conductivity (~ 0.01 S/cm) and fast-relaxing (ion relaxation time in micro seconds) electrolytes having wide electrochemical stability window (~ 3 V). Resistance of highest conducting sample, having 0.8 mm thickness and 1 × 1 cm2 area is ~ 6 Ω. The synthesized electrolyte is easily moldable in desired shape and size and hence devices may be fabricated with smaller equivalent series resistance. The estimated relaxation time is 62 μs indicating that fabricated devices will be able to deliver energy in shorter time. The approximate preparation cost of the material (1 × 1 × 0.08 cm3) is INR 20 (~ 0.3USD). The low cost, good technical parameters, and flexibility make it a promising material for electrochemical device fabrication. [ABSTRACT FROM AUTHOR]

A number of clinical findings suggested HDL-raising as a plausible approach to treat residual risk of CVD. However, lack of CVD risk reduction by elevated HDL cholesterol (HDL-C) through cholesterol ester transfer protein (CETP) inhibition and enhanced risk reduction in apolipoprotein A-I Milano (apoAI-M) individuals with low HDL-C shifted the focus from HDL-C level to HDL function. In the present study, we investigated correlations between HDL-C, HDL function, fecal cholesterol excretion, and ex vivo plasma cholesterol efflux capacity (CEC) in animal models using two HDL modulators, LXR and PPAR-α agonists. In C57Bl mice, LXR agonist, T1317, raised HDL-C by 30%, while PPAR-α agonist, fenofibrate, reduced HDL-C by 30%, but fecal cholesterol showed twofold increase in both cases. CEC showed a 30–40% increase. Combination of LXR and PPAR-α agonists showed no changes in HDL-C, but, interestingly, fecal cholesterol increased by 4.5-fold, and CEC by 40%, suggesting existence of additional pathway for fecal cholesterol excretion. Regression analysis showed a lack of correlation between HDL-C and fecal cholesterol and CEC, while fecal cholesterol showed significant correlation with CEC, a measure of HDL function. ABCA1 and G1, the two important players in RCT showed greater induction with LXR agonist than PPAR-α agonist. HDL-C increased by 40 and 80% in LXR and PPAR-α treated apoA-I transgenic mice, respectively, with 80% increase in fecal cholesterol. A fivefold increase in fecal cholesterol with no correlation with either plasma HDL-C or CEC following co-treatment with LXR and PPAR-α agonists suggested existence of an HDL-independent pathway for body cholesterol elimination. In hyperlipidemic diabetic ob/ob mice also combination of LXR and PPAR-α agonists showed marked increases in fecal cholesterol content (10–20-fold), while HDL-C rise was only 40%, further suggesting HDL-independent elimination of body cholesterol in mice treated with combination of LXR and PPAR-α agonists. Atherosclerosis attenuation by LXR and PPAR-α agonists in LDLr-deficient mice was associated with increased fecal cholesterol, but not HDL-C. However, fecal cholesterol counts showed inverse correlation with aortic cholesteryl ester content. These data suggest: (a) lack of correlation between HDL-C and fecal or aortic cholesterol content; (b) HDL function (CEC) correlated with fecal cholesterol content; (c) association of reduced aortic lipids in LDLr−/− mice with increased fecal cholesterol, but not with HDL-C, and (d) existence of an HDL-independent pathway for fecal cholesterol excretion following co-treatment with LXR and PPAR-α agonists. [ABSTRACT FROM AUTHOR]

In this paper, the performance of an energy detector in cognitive radio, using different diversity combining techniques, is evaluated. Among many diversity combining techniques, maximal ratio combining (MRC) gives the best results but at the cost of the highest complexity. To design a simpler receiver, it is suggested to use less complex combining techniques, i.e. switched diversity, which provides one of the least complex solutions to combat fading. The paper analyzes two switched diversity schemes, switch examine combining (SEC), and switch examine combining with post examining selection (SECp). A closed form expression determining the probability of detection using MRC, SEC and SECp is derived for various numbers of branches. Detection performance with different diversity combining techniques is compared and the complexity trade-off is observed. [ABSTRACT FROM AUTHOR]

To perform spectrum sensing in fading environment is one of the most challenging tasks for a CR system. Diversity combining schemes are used to combat the effect of fading and hence detection probability of CR gets improved. Among many diversity combining techniques, switched diversity offers one of the lowest complexity solutions. The receiver embedded with switched diversity looks for an acceptable diversity path (having signal to noise ratio (SNR) above the required threshold) to receive the data. In conventional switch and examine combining (SEC) scheme, when no acceptable path is found after all the paths are examined, the receiver randomly chooses an unacceptable path. Switch and examine combining with post-examining selection (SECp) is a modified version of conventional SEC. In SECp, the conventional SEC scheme is altered in a way that it selects the best path when no acceptable path is found after all paths have been examined. In this paper, formula for probability of detection () is derived using SECp and SEC diversity combining technique over Rayleigh fading channel. Also the performance of SECp is compared with SEC and no diversity case. Performance comparison is done with the help of SNR vs.and complementary receiver operating characteristic curves. [ABSTRACT FROM AUTHOR]

An environment friendly coupled mode surface plasmon resonance sensor structure with starch biofilm as sensing element for humidity detection of environment is fabricated and demonstrated. The surface plasmon resonances were created using PVC layer fabricated between silver and starch biofilm on a rectangular prism. The analyses of fabricated sensor have been done by both wavelength and angular interrogation methods. The proposed sensor has maximum sensitivity 0.45 nm/%RH in wavelength interrogation method and 0.09°/%RH in angular interrogation method. Here the variations in humidity of environment, changes the refractive index of starch biofilm and hence in the surface plasmon resonances. Also, the proposed sensor shows a linear variation in resonance wavelength and resonance angle with respect to the variation in humidity of environment. [ABSTRACT FROM AUTHOR]

Energy storage devices are the lifeline of today's society, and hence, researchers are trying to achieve 3Es (economical, environment friendly, and easy to prepare) along with other required technical data. Here, a new wheat starch + NaI system is synthesized which not only have good technical data such as high ionic conductivity (3.61 × 10 S/cm), very low dielectric relaxation time (13.2 μs), and wide electrochemical stability window (2.6 V) but it also satisfies 3Es conditions because it uses starch which is very cheap and abundant biopolymer available in large variety. The approximate cost of preparing 1 cm of the sample is approximately INR 15. The prepared material is flexible, free standing film which can be easily stretched to 1.9 times to its length, and can be easily twisted up to 90°. The phase angle value approaches to −73° and maintains its value from 10 Hz to 9 kHz frequency range. The ESR value (of sample having thickness 0.48 mm and area 1.21 cm) is very low (1.10 Ω). Parallel capacitance (C) to series capacitance (C) ratio is >0.9, and the value is maintained up to a wide frequency range (10 Hz to 10 kHz). Self-resonance frequency (the frequency limit below which energy can be stored efficiently) is also quite high (0.1 MHz) for the present system. Hence, the studied system is a potential candidate for future electrochemical applications. [ABSTRACT FROM AUTHOR]

Issues concerning the works of Indian novelist Amitav Ghosh are discussed with particular emphasis on his book, In An Antique Land. This book unlike his earlier works is not a novel, but a mixture and has its origins in Ghosh's doctoral thesis.