Miniaturised sharp rejection bandpass filter with reconfigurable bandwidth for UWB applications

A novel, compact and highly selective microstrip bandpass filter with bandwidth reconfigurability for ultra-wideband (UWB) applications is presented. The proposed design uses stepped impedance resonator (SIR) for realization of bandpass filter (BPF) and employs a single varactor diode (BB135-NXP) for the purpose of reconfiguring bandwidth. Additionally, to improve the selectivity between passband edges, a cross-coupling between I/O feed lines is introduced which generated pairs of attenuation poles at each side of the passband. Measurements on a fabricated reconfigurable filter confirm the accuracy of the design procedure. Measured responses show good agreement with simulation. The proposed filter is able to achieve significant size reduction (8.5 mm �� 7.1 mm excluding the feeding ports) as compared to the conventional bandpass filters with reconfigurable bandwidth.

Hollywood and world cinema influences: tracing intertextuality in the works of two contemporary filmmakers from Francophone Africa; Mahamat Saleh Haroun and Abderrahmane Sissako

Don���t tell me the moon is shining; show me the glint of light on broken glass Anton Chekhov Representations of Africa in cinema are almost as old as cinema itself and date back to Hollywood���s silent era. Most early examples feature the continent as a mere exotic backdrop and include The Sheik (Melford 1921), soon followed, in 1926, by George Fitzmaurice���s Son of the Sheik starring Rudolph Valentino. The next decade brought Van Dyke���s Tarzan movies, Robert Stevenson���s King Solomon���s Mines (1937), and, on the European side, Duvivier���s P��p�� le Moko (1936). For representations of Francophone Africa by Africans themselves, the viewing public more or less had to wait, however, until decolonisation in the 1960s (with, for example, Sembene Ousmane���s Borom Sarret and La Noire de���, both released in 1966 and, in 1968, Mandabi). Since then Francophone African cinema has come a long way and has diversified into various strands. Between Borom Sarret and Mahamat-Saleh Haroun���s 2006 Daratt, Saison s��che - or the same director���s Un homme qui crie, almost half a century has elapsed. Over this period, films inevitably have addressed a spectrum of visual, ideological and political tropes. They range from unadorned depictions of the newly independent states and their societies to highly aestheticised productions, not to mention surreal and poetic visions as displayed for instance in Djibril Diop Mamb��ty���s Touki Bouki (1973). Most of the early films send an overt socio-political message which is a clear and explicit denunciation of a corrupt state of affairs (Souleymane Ciss�����s Baara, 1977). They aim to trigger strong emotional and political responses from the viewer, in unambiguous support for the film-maker���s stand. Sembene himself declared: ���I consider cinema a means of political action��� (Murphy 2000: 221). Similarly, the Mauritanian director Med Hondo wishes to ���take up this technical medium and to make it a mouthpiece on behalf of [his] fellow Africans and Arabs��� (Jeffries 2002: 11). All this echoes the claims of the F��d��ration Panafricaine des Cin��astes (FEPACI, founded in 1969), an organisation ���dedicated to the liberation of Africa���. In sharp contrast to the incipient momentum given Francophonie by Bourguiba, the Nigerien Hamani Diori and the Senegalese Senghor, who invoked a worldwide communaut�� organique francophone, FEPACI called for ���the creation of an aesthetics of disalienation��� [using] didactic... forms to denounce the alienation of countries that were politically independent but culturally and economically dependent on the West��� (Diawara 1996: 40). Sembene���s Xala (1974) became the blueprint for this, to this day the best-known vein of Francophone African cinema. Thus considered, this pedigree seems a million miles from mainstream global cinema with its overriding mission to entertain. A question therefore arises: to what extent can a cinema that sprang from such beginnings be seen to interface in any meaningful way with a global film industry that, overwhelmingly and for a century, has indeed entertained the world ��� with Hollywood at its centre?

Reforms, incentives, welfare and productivity growth in Chinese wheat production

Following the 1978 rural reform, a series of agricultural reforms were introduced in China with an aim to create incentives for the farmers to produce more. However, the nineties��� reforms towards liberalization eventually resulted in a huge drop in agricultural production, which apparently motivated the grain self-sufficiency program in 1998. For a dataset that covers wheat production during these reforms, we examine how and to what extent these reforms affected the Total Factor Productivity (TFP) and the welfare of wheat farmers in China, both at the national and at the regional level. We find that although the nineties' price reforms led to a relatively faster growth of the incentivized TFP of wheat production, they failed to improve profits vis a vis welfare for the farmers. A series of weather shocks in the early nineties resulted in a scarcity of cultivable land and a shortage of agricultural labour, which eventually led to a sharp increase in their relative prices. The introduction of grain self-sufficiency program stabilized these agricultural prices but destroyed the growth in TFP for most regions. However, this reform resulted in some improvement in farmers��� welfare. Wheat farmers in China therefore experienced a trade off between productivity and welfare; competition boosted their productivity and regulation improved their welfare. Not only these findings add a completely new set of results to the existing literature, they can also form a strong basis for future agricultural reforms in China.