To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
This Paper reveals a novel single layer five band frequency selective surface (FSS). Novelties of the proposed FSS lie in its five closely spaced stop bands at 2.4, 3.38, 4.82, 6.32, and 7.75 GHz as well as the reduced single layer structural thickness (0.0016 λ0) and the miniaturized unit cell size (0.0656 λ0) at lower resonant frequency as compared to the existing multiband FSS. The unit cell structure consists of six octagonal concentric interconnected loops. Adjacent loop interconnection technique reduces the cell size by more than 44%. Furthermore, arrow-shaped rings are also introduced on each corner of the outermost octagonal loop, and using this technique approximate 23% cell miniaturization can be achieved. In addition, the proposed FSS exhibits excellent angular stability.
The effects of La-substitution into SrTiO3 (STO) perovskite oxides on their phase structure, formation enthalpy and electrical conductivity have been investigated. La substitution in STO has been reported to show a significant enhancement in electronic conductivity in a wide-band-gap layered perovskite compound STO. Mixture of Lanthanum and Titanium oxide may lead to various phases including La2/3TiO3, La2Ti2O7 and La2TiO5. In this work, more than 50 structural models have been constructed by considering ionic state substituents, distance between substituents and their concentrations. We investigated the formation enthalpy, elastic properties and band gap by density functional theory (DFT) calculations. We have also investigated the effect of reducing environment on La2/3TiO3. The computed bulk modulus (∼2.4 % deviation) and band gap (∼12% deviation) of STO are in good agreement with the literature. Our results indicate that La substitution into STO could significantly reduce the band gap. Reduction in band gap is maximum when the substituents is present at low concentrations. Internal position of La substituents in STO affects the band gap marginally while energy remains almost same. Formation enthalpy of La2/3TiO3 from LaTiO3 is around 2 eV. La2/3TiO3 acts as band insulator (band gap = 2.8 eV). In reducing environment, the band gap of La2/3TiO3 significantly reduces. Sr substitution in La2/3TiO3 lower the band gap and formation enthalpy. La2Ti2O7 and La2TiO5 have higher band gap and lower bulk modulus than STO. Sr substitution is not feasible in La2Ti2O7 and La2TiO5.
The large ribosomal subunit has a distinct feature, the stalk, extending outside the ribosome. In bacteria it is called the L12 stalk. The base of the stalk is protein uL10 to which two or three dimers of proteins bL12 bind. In archea and eukarya P1 and P2 proteins constitute the stalk. All these extending proteins, that have a high degree of flexibility due to a hinge between their N- and C-terminal parts, are essential for proper functionalization of some of the translation factors. The role of the stalk proteins has remained enigmatic for decades but is gradually approaching an understanding. In this review we summarise the knowhow about the structure and function of the ribosomal stalk till date starting from the early phase of ribosome research.
Oral Democracy studies citizens' voices in civic and political deliberations in India's gram sabhas (village assemblies), the largest deliberative institution in human history. It analyses nearly three hundred transcripts of gram sabhas, sampled within the framework of a natural experiment, allowing the authors to study how state policy affects the quality of discourse, citizens' discursive performances and state enactments embodied by elected leaders and public officials. By drawing out the varieties of speech apparent in citizen and state interactions, their analysis shows that citizens' oral participation in development and governance can be improved by strengthening deliberative spaces through policy. Even in conditions of high inequality and illiteracy, gram sabhas can create discursive equality by developing the 'oral competence' of citizens and establishing a space in which they can articulate their interests. The authors develop the concept of 'oral democracy' to aid the understanding of deliberative systems in non-Western and developing countries. This title is also available as Open Access.
This article presents an ethnography of a contemporary residential madrasa for teenage Muslim girls in a North Indian town undertaken by a team of two researchers. We focused on different aspects of the overall study, with Sanyal conducting participant observation within the madrasa and Farah interviewing a select number of graduates and former students in their home environments. The result is a comprehensive picture of the madrasa's transformative role in the socio-religious lives of its students, which highlights the importance of the connections between the madrasa and the home.
Of significance are the religious and denominational orientation of the madrasa—Barelwi Sunni Muslim—as well as the working-class status of the girls and their parents’ low level of education. With limited resources, the madrasa inculcates in the students, and by extension their neighbourhoods and wider communities, a new awareness of religious duties and mutual obligations, and gives its students confidence and a voice within both their families and communities. The long-term potential impact of madrasas such as this one appears to be significant in contemporary North India.
This article presents a compact novel quasi-self-complementary semi-octagonal-shaped antenna for ultra-wideband (UWB) application. The proposed novel structure is fed by a microstrip line where different rectangular truncation is etched to the ground plane as an impedance matching element, which results for much wider impedance bandwidth (VSWR<2) from 2.9 to 20 GHz. In order to obtain band-notched characteristics at 5.5 GHz, an open-ended, quarter wavelength, spiral-shaped stub is introduced in the vicinity of the truncated part of the ground plane. An equivalent circuit model is adopted to investigate the band rejection characteristics of the ground plane stub. Sharpness of the rejection band can be controlled by maintaining the gap between stub resonator and the slotted periphery of ground plane. The proposed antenna design is validated by experimental measurements.
This paper presents the dual band notch characteristics of Ultra wideband (UWB) monopole antenna. Proposed antenna (30 × 30 mm2) consists of arrow shaped patch and truncated ground plane. Operating range of the proposed antenna (voltage standing wave ratio < 2) is 2.2–11 GHz. In order to achieve dual band stop characteristics, λ/2 open ended angularly separated slit pair has been inserted on the radiator for world interoperability for microwave access (WIMAX) (3.3–3.9 GHz) band rejection performance and wireless local area network (WLAN) (5.1–5.9 GHz) band rejection has been realized by introducing a pair of angularly separated λ/2 conductor backed plane (CBP). Using proper adjustment of angular separation for both slit pair and CBP pair, enhanced band rejection can be achieved for the WIMAX and WLAN band, respectively. The performance of antenna has been investigated in terms of frequency domain and time domain to assess its suitability in UWB communication.
To test the hypothesis that modulation of hepatic microsomal sulphoxidation and sulphonation by the cytochrome P450 inhibitor piperonyl butoxide could increase bioavailability of albendazole, the present study was undertaken to understand the pharmacokinetics of albendazole in goats at a dose of 7.5 mg kg− 1 body weight with and without co-administration with piperonyl butoxide at 63.0 mg kg− 1 body weight. Plasma albendazole sulphoxide metabolite, the anthelmintically active moiety, reached its maximum concentration of 0.322 ± 0.045 μg ml− 1 and 0.384 ± 0.013 μg ml− 1 at 18 h and 24 h after administration of albendazole alone and co-administration of albendazole with piperonyl butoxide, respectively. Analysis of the data revealed statistically increased albendazole sulphoxide levels at 24 (P < 0.001), 30 (P < 0.001) and 36 h (P < 0.01) after administration of albendazole with piperonyl butoxide, with statistically increased levels of albendazole sulphone at 24, 30 and 48 h after administration. No significance difference (P > 0.05) in values of maximum concentration (normal and calculated) could be observed between groups of goats. However, values of time to reach the concentration maximum (normal and calculated), area under the concentration–time curve (0–∞ and calculated), minimum residence time, distribution half-life, elimination half-life and total area under the first movement of plasma drug concentration–time curve were significantly higher (P < 0.05) in plasma levels of albendazole sulphoxide in goats following single oral co-administration of albendazole with piperonyl butoxide. The faecal egg count reduction and lower 95% confidence limit for the group treated with albendazole alone were 97 and 68%, while for co-administration of albendazole and piperonyl butoxide the values were 99 and 97%, respectively. The ED50 for egg hatch was 0.196, indicating suspected resistance to benzimidazole anthelmintics. The drug combination proved efficacious against an albendazole-resistant nematode parasite population in goats.
The influence of diet type and pre-treatment fasting on the kinetic disposition of albendazole was evaluated in Sahiwal heifers following oral and intra-ruminal administration of the drug. The anthelmintically active moiety albendazole sulphoxide appeared early and was eliminated early in cattle offered green fodder, with decreased maximum concentration (Cmax) and area under concentration–time curve (AUC) when the drug was administered both through oral and intra-ruminal routes. Further, the elimination half-life (t½β) revealed significantly increased values for albendazole sulphoxide in cattle administered albendazole through the intra-ruminal route. An increased AUC and t½β is reflective of increased bioavailability of albendazole in animals offered dry fodder. Increased values (P < 0.05) of Cmax, time to Cmax (Tmax), AUC and t½β for albendazole sulphoxide occurred in cattle with a pre-treatment 24-h fast, resulting in its increased bioavailability. Extrapolation of data of the active metabolite albendazole sulphoxide levels in terms of drug–parasite contact revealed increased exposure of parasites to the drug in cattle administered albendazole through the intra-ruminal route and with 24-h pre-treatment fasting.