Monolithic Microwave Integrated GaAs Electromagnetically-Coupled Antenna

Monolithic antenna on GaAs to be used in miniature active sensors is presented. After a first study of technological processes and the characterisation of various substrates in K-band, the feasibility of an antenna, operating in K-band, electromagnetically-coupled and integrated on GaAs by monolithical realisation, has been demonstrated. A low profile (1mm) and wide bandwidth (2.3 GHz around 25 GHz) antenna is obtained

Qualitative Behavioural Assessment of Bos indicus cattle after surgical castration

There are various methods to perform castration of cattle, but surgical castration is the most common. Although it is well documented that surgical procedures inflict pain, analgesic use is usually omitted for surgical castration of production animals in Australia. This study compares the behavioural responses of castrated cattle (C) with non-castrated (NC) controls, and C with those castrated and given lignocaine and meloxicam (CLM) for analgesia. Brahman bull calves (n = 8 for each treatment) were filmed in the morning pre- (day -1) and post- (day +1) castration in the paddock and feed yard (‘context’ of observation). Over four sessions, volunteer observers viewed the video footage for Qualitative Behaviour Analysis (QBA) using the Free Choice Profiling methodology comparing C and NC cattle, and C and CLM cattle under both contexts. The QBA consensus profiles explained 37.4% (C vs. NC) and 40.6% (C vs. CLM) of variation among observers for paddock sessions and 34.7% (C vs. NC) and 38.7% (C vs. CLM) for feed yard sessions. Significant treatment x day interaction effects were recorded in the paddock (P = 0.007 and P < 0.001) and yard (P =  0.004 and P =  0.025) contexts for comparisons between NC vs C, and C vs CLM respectively. Compared to NC, post-castration C cattle were described as more ‘bored’/’lethargic’ and ‘alone’ (paddock) and were more ‘calm’/’relaxed’ and ‘relaxed’/’lonely’ (yard). Similarly, compared to CLM, post-castration C cattle were described as more ‘docile’/’chilled’ and ‘curious’/’aware’ (paddock) and were less ‘hungry’/’alert’ (yard). There was only one correlation between qualitative and quantitative behaviour scoring; ruminating showed significant correlation with one dimension in each context, that reflected a positive emotion (‘calm, relaxed’). The comparison between C vs. NC suggest that C were less active and less engaged with their environment compared to the NC group following castration. The C vs. CLM comparison suggests a more subtle response whereby analgesia was associated with more positive valence (higher scores on ‘calm/comfortable’, and ‘hungry/alert’ dimensions) following castration. The interpretation of findings requires careful consideration of the emotional responses given these calves were unhabituated and reactive to their surroundings. These results suggest the body language of Bos indicus cattle may reveal indicators of pain, and that the administration of analgesia may be beneficial at the time of castration. The study highlights the complexities and challenges of identifying pain responses in Brahman cattle

Wideband compact antenna for K-band applications

A compact coupled microwave active antenna is presented. This antenna is proximity fed, and consists of a square radiating element array on a polymer dielectric layer. The compactness of the antenna is obtained through technological optical processes and the parasitic patch phenomenon which increases the bandwidth

Antennes intégrées multicouches. Caractérisation diélectriques et applications

Des procédés de réalisation d’antennes micro-ondes en technologie micro-rubans multicouches sont décrits. La gamme de fonctionnement des antennes s’étend jusqu’à 24 GHz. Une méthode originale de caractérisation à 24 GHz des propriétés diélectriques de la couche émissive de l’antenne est exposée. Un procédé innovant de réalisation de films diélectriques destinés à la conception d’antennes actives est exposé, ainsi que sa caractérisation de 2.45 à 24 GHz

Adjuvant high-dose medroxyprogesterone acetate for early breast cancer: 13 years update in a multicentre randomized trial

The authors updated their report on a randomized trial initiated in 1982 comparing, in early breast cancer, high-dose IM Medroxyprogesterone acetate (HD-MPA) adjuvant hormonotherapy during 6 months with no hormonotherapy; node-positive patients also received 6 courses of IV CMF (day 1, day 8; q.4 weeks). 246 node-negative (NN) and 270 node-positive (NP) patients had been followed for a median duration of 13 years. Previous results were confirmed in this analysis on mature data. In NN patients, relapse-free survival (RFS) was improved in the adjuvant hormonotherapy arm, regardless of age while overall survival (OAS) was also increased in younger (less then 50 years) patients. In the whole group of NP patients, no difference was seen regarding RFS or OAS. However, an age-dependant opposite effect was observed: younger patients (< 50) experienced a worse and significant outcome of relapse-free and overall survivals when receiving adjuvant HD-MPA while older patients (> = 50) enjoyed a significant improvement of their relapse-free survival. For both NN and NP patients, differences in overall survivals observed in older women with a shorter follow-up, were no longer detected. © 2001 Cancer Research Campaign http://www.bjcancer.co

Use of the Robson classification to assess caesarean section trends in 21 countries: a secondary analysis of two WHO multicountry surveys

Background: Rates of caesarean section surgery are rising worldwide, but the determinants of this increase, especially in low-income and middle-income countries, are controversial. In this study, we aimed to analyse the contribution of specific obstetric populations to changes in caesarean section rates, by using the Robson classification in two WHO multicountry surveys of deliveries in health-care facilities. The Robson system classifies all deliveries into one of ten groups on the basis of five parameters: obstetric history, onset of labour, fetal lie, number of neonates, and gestational age. Methods: We studied deliveries in 287 facilities in 21 countries that were included in both the WHO Global Survey of Maternal and Perinatal Health (WHOGS; 2004–08) and the WHO Multi-Country Survey of Maternal and Newborn Health (WHOMCS; 2010–11). We used the data from these surveys to establish the average annual percentage change (AAPC) in caesarean section rates per country. Countries were stratified according to Human Development Index (HDI) group (very high/high, medium, or low) and the Robson criteria were applied to both datasets. We report the relative size of each Robson group, the caesarean section rate in each Robson group, and the absolute and relative contributions made by each to the overall caesarean section rate. Findings: The caesarean section rate increased overall between the two surveys (from 26·4% in the WHOGS to 31·2% in the WHOMCS, p=0·003) and in all countries except Japan. Use of obstetric interventions (induction, prelabour caesarean section, and overall caesarean section) increased over time. Caesarean section rates increased across most Robson groups in all HDI categories. Use of induction and prelabour caesarean section increased in very high/high and low HDI countries, and the caesarean section rate after induction in multiparous women increased significantly across all HDI groups. The proportion of women who had previously had a caesarean section increased in moderate and low HDI countries, as did the caesarean section rate in these women. Interpretation: Use of the Robson criteria allows standardised comparisons of data across countries and timepoints and identifies the subpopulations driving changes in caesarean section rates. Women who have previously had a caesarean section are an increasingly important determinant of overall caesarean section rates in countries with a moderate or low HDI. Strategies to reduce the frequency of the procedure should include avoidance of medically unnecessary primary caesarean section. Improved case selection for induction and prelabour caesarean section could also reduce caesarean section rates

Nature of conduction in doped silicon

Via ultrafast optoelectronic THz techniques, we are able to test alternative theories of conduction by precisely measuring the complex conductivity of doped silicon from low frequencies to frequencies higher than the plasma frequency and the carrier damping rate. These results, obtained for both n and p-type samples, spanning a range of more than 2 orders of magnitude in the carrier density, do not fit any standard theory. We only find agreement over the full frequency range with the complex conductivity given by a Cole-Davidson type distribution applied here for the first time to a crystalline semiconductor, and thereby demonstrate that fractal conductivity is not just found in disordered material.Peer reviewedElectrical and Computer Engineerin

Carrier dynamics of electrons and holes in moderately doped silicon

A time-domain spectroscopic technique, based on the generation and detection of a collimated beam of subpicosecond broadband terahertz pulses, is used to measure the absorption and dispersion of n- and p-type silicon, with resistivities of 0.1, 1, and 10 Ohm-cm in the submillimeter range of 0.1-2 THz. From the transmission measurements performed at room temperature and at 80 K, the absorption and dispersion, and concomitantly the full complex conductivity, of the doped silicon could be obtained. The results provide an accurate view on the dynamics of the electrons and the holes. Although the simple Drude model, with an energy-independent relaxation time, gives a surprisingly accurate description of the observed carrier dynamics, the measurements do show that some refinements are needed. An extended model, with an energy-dependent carrier-relaxation rate, can explain most of the observed deviations from the simple Drude model.Peer reviewedElectrical and Computer Engineerin

Narrowband active GaAs MMIC filters in K-band

Active GaAs MMIC filters in K-band, around 22 GHz, have been designed, realised and characterised. Simulation and measurement results are compared and agree. The best performances measured for a band-pass filter centered at 21.98 GHz are a bandwidth of 0.75 GHz and a noise figure of 1.95 dB